Question # 1

For keeping a body in circular motion,the force required is

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Centripetal

Centrifugal

Radial

Tangential

When a strength changes the length of a body,it is called

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Tensile stress

Shear stress

Compressional stress

The word amorphous means:

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Without any structure

With define structure

Regular arrangement of molecules

Both B and C

None of these

The unit Compton wavelength is same as:

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Compton wavelength

Compton frequency

Compton shift

Both (a) & (b)

A thin layer of oil on the surface of water looks colored due to:

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Diffraction of light

Reflection of light

Dispersion of light

Interference effect of light

The petrol engine works on the basis of

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Kelvin statement

Clausius statement

Carnot cycle

First law of thermodynamics

When the same object is viewed at a shorter distance the image on the retina of eye is ______ and so the object appears ______

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Greater, small

Smaller, smaller

Smaller, larger

Greater, larger

For glass-air boundary, the value of the critical angle is

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42°

45°

30°

60°

Intensities of the two waves of light are I and 4I.The maximum intensity of the resultant wave after superposition is

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5I

9I

16I

25I

The escape velocity of mercury in Kms^-1

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1.29

3.24

4.02

4.3

When a radioactive nucleus emits a 𝖰 −paritcles, the mass number of the atom:

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Increases by one

Decreases by one

Remains the same

Decreases by four

A rubber cord 100 cm long is elongated 1 cm by a stretching force of 0.2 N. The cross-sectional area of the cord is 0.04 cm². Find the Young's modulus for that rubber.

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0.5 N cm^-2

0.05 N cm^-2

50 N cm^-2

500 N cm^-2

According to boyle's law, volume of a given mass of a gas is

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Inversely proportional mass at constant pressure

Directly proportional to pressure at constant temprerature

Inversely proportional pressure at constant temprature

None of these

The S.I. unit of permitivity are

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Nmc^-2

C² N^-1 m^-2

Nm² C^-2

NmC^-1

The energy of molecular motion appears in the form of

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Friction

Heat

Viscosity

Potential energy

As cross-sectional area of the pipe decreases the speed of fluids must increase according to

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Bernoulli's equation

Venture's reaction

Equation of continuity

Torricelli's theorem

The information carrying capacity in an optical fibre is called

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wavelength

frequency

bandwidth

none of them

Consider a spherical shell of metal at he centre of which a positive point charge is kept

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The electric field is zero outside the shell

The electric field is zero everywhere

The electric field is zero in the region inside the shell

The electric field is non-zero in both regions outside and inside the shell

A certain noninverting amplifier has R1 of 1 kΩ and R2 of 100 kΩ. The closed-loop voltage gain is ………

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100,000

100

1000

101

The resolving power of human eye is

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1°

2°

3°

6°

A satellite moving round the earth constitutes

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Inertial frame of reference

Non-inertial frame of reference

Neither inertial nor non inertial

Both A, B

Which force is the medium independent force ?

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Electrostatic force

Nuclear force

Gravitational force

All of them

An electric fan rotating in 3 revs^-1 is switched off. It come sot rest in 18.0 sec. Find the value of acceleration which is

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+ 1.267 revs^-2

0027 revs^-2

- 0.167 revs^-2

- 0.152 revs^-2

The rate at a which the angular displacement is changing with time is called

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Angular acceleration

Angular velocity

Average angular velocity

None of these

Which one the following gives three regions of electromagnetic sepctrum in order of increasing wavelength?

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Gamma rays, micro waves, visible light

Radio waves, ultraviolet waves, X-rays

Ultraviolet rays, Infrared rays, micro waves

Visible light, gamma rays, radio waves

In YDS experiment, condition for constructive interference is that path difference is equal to

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nλ

mλ

(n + 1/2)λ

(m + 1/2)λ

Impulse is the force applied for a very short interval time in which force is

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Constant

Not constant

May be constant for some time

None of these

Two bodies A and B each of mass 2 kg moving towards right collide with each other elastically,after collision

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A stops and velocity of B increases

Velocity of both decreases

Both moves with the same velocity

Both interchange their velocities

Which does not show polarization

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Longitudinal wave in gas

Transverse wave in gas

Both a and b

None of these

In a full wave rectifier with input frequency 50Hz. The frequency of pulsating D)C) received as an output across the load is

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50 Hz

100 Hz

500 Hz

zero

Which of the following quantities is / are scalar ?

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Dipole moment

Electrical permitivity

Electric field

Electrical potential

The only significant motion possessed by the mono-atomic gas molecules is:

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Translatory

Rotatory

Vibratory

None of these

In a full wave rectifier, the diode conducts during

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Both halves of the input cycle

A portion of the positive half cycle of the input

Positive half cycle of the input

Both halves of the input cycle

Light year is the unit of

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Speed

Mass

Distnace

Time

When the light from two lamps falls on a screen, no interference pattern can be obtained. Why is this?

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the light from the lamps is white

the lamps emit light of different amlitudes

the light from the lamps is not coherent

the lamps are not point sources

Huygen's wave front which sends out secondary wavelets with a speed equal to

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Speed of propagation of the wave

Speed of propagation greater than wave

Speed of propagation less than the wave

None of these

The frame of reference in which Newton first law of motion holds is known as

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Inertial frame of reference

Non-Inertial frame of reference

Every frame of reference

None of these

The total linear momentum of an isolated system remains

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Constant

Variable

Zero

None of these

Two masses of 1 g and 4 g are moving with equal kinetic energies.The ratio of the magnitudes of their linear momenta is:

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4 : 1

√2 : 1

1 : 2

1 : 16

Compton Effect makes the use of the law of conservation of:

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Energy

Momentum

Charge

Both (a) & (b)

If the distance of separation between two chares is increased,the electrical potential energy of the system will

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Increase

Decrease

May increase or decrease

Remain the same

Spokes used in a bicycle wheel increase its

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Moment arm

Moment of inertia

Acceleration

Velocity

The pressure P of a gas at constant temperature varies with its density P

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Directly

Inversely

Equal

None of these

The principle of rocket motion is based on the

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First law of motion

Second law of motion

Third law of motion

None of these

A fixed mass of a gas is at a pressure P. if its volume and absolute temperature are both doubled, the new pressure is

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P/4

P/2

P

2P

In order to perform experiment, Davisson and Germer used accelerating voltage of:

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54V

120V

220V

400V

A person holds a bucket of weight 60 N He walks 7 m along the horizontal then climbs up a vertical distance of 5m. The work done by the man is

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300 j

720 j

420 j

None

When the velocity of the car is constant. The velocity time graph is a

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Straight line

Straight line rises the same height for equal intervals of tome

Horizontal straight line

None of these

The dimensions of the quantities in one of the following pairs are the same.identify the pairs.

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Torque and work

Angular momentum and work

Energy and Young's modulus

Light year and time

The danger signals are red while the eye is more sensitive to yellow because

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Scattering in yellow colour is less than that of red

Red light is longer in wavelength than yellow light

Scattering in red is less than that of in yellow

Red colour has greater frequency than yellow light

No entropy change is associated with:

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Isothermal

Adiabatic process

Isobaric process

None of them

The magnitude of i² in scalar product is

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Zero

1

Less than 1

Greater than 0

Xerography means

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Type writing

Wet writing

Dry writing

None of these

The theory which explains the vast diversity in an electrical behaviour of all types the materials is

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Free electron theory

Band theory

Theory based as chemical properties

None of these

A semi conductor in its extremely pure from is known as

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extrinsic semi-conductor

intrinsic semi-conductor

either of them

none of them

When crest of one wave falls on the crest of the other wave. This phenomenon is known as:

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Destructive interference

Diffraction

Polarization

Constructive interference

Surface tension of water is due to

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Inter molecular attractions

Intermolecular spaces

Inter molecular repulsion

None of above

The relative velocity of a particle moving with velocity V with respect to itself is

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Zero

V

-V

None of these

The unit vectors is not restricted to Cartesian coordinate system only. Unit vectors may have

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Specific direction

Any direction

Not a and b

None of these

If we go above the surface of earth equal to the radius of earth than value of g

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g

g/4

g/9

g/2

An n-type semiconductor is obtained by doping germanium or silicon with

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Tetravalent impurity

Trivalent impurity

Pentavalent impurity

Monovalent inpurity

At the point of contact of the lens and the glass plate, the incident and reflected rays interfere

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constructively

destructively

either of them

none of them

In 420 days, the activity of a sample of polonium (Po) fell to one-eight of its initial value. The half-life of polonium is :

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140days

45days

87days

90days

A collision in which the K.E. is not conserved is called

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Elastic collision

Inelastic collisiion

Both

None of these

The product of force and time of impact force is called

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Momentum

Impulsive force

Impulse

Rate of change of momentum

The displacement coincides with the path of the motion when a body moves in a

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curved line

straight line

either straight or curved

none of them

For a rocket the change in momentum per second of the ejecting gases is equal to

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Acceleration of rocket

Velocity of rocket

Force acting on rocket

Momentum of rocket

Dimensions of light year are

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[LT^-1]

[ML^-1T]

[ML^-1]

[M⁰L]

Mathematically the instantaneous velocity is defined as

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The moment of linear momentum of a body is called

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Angular momentum

Couple

Impulse

Torque

In case of point source of light, shape of wavefront is:

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Spherical

Cylindrical

Plane

None of these

If it is assumed that a frictional force f is present, during the downward motion their

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mgh - f = 1/2 mV²

2mgh - f = 1/2 mV²

mgh - f = 1/2 mV²

None of these

Stress is defined in terms of:

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Applied force

Deformation

Formation

Any of these

None of these

Taking the earth to be a spherical conductor of diameter 12.8 x 10³ km its capacity will be:

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711 μF

611 μF

811 μF

511 μF

The relative permitivity ∈_r for rubber is

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2.8

3.0

2.90

2.94

Approximate power of Jumbo. Let Aircraft in watts.

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1.2 × 10⁶

1.3 × 10⁸

1.2 × 10⁸

1.1 × 10⁹

Even the small viscosity of the air causes a retarding force on car at high speed is

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Small

Large

Very large

None of these

The centre of gravity of an object is

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The force of gravity on the object

The point about which the object rotates

The point at which the total weight of the object act

none of these

For fast moving particles, such as atomic particles in an accelerator, the following branch of physics is applicable

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newtonian mechanics

classical mechanics

relativistic mechanics

all of them

The Earth axis of rotation is

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Remains fixed

Remains fixed in one direction

Not fixed

None of these

On applying a stress of 20 x 10⁸Nm^-2, the length of perfectly elastic wire is doubled. Its young' modulus is

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40 x 10⁸N/m²

20 x 10⁸N/m²

10 x 10⁸N/m²

5 x 10⁸N/m²

The image formed by an eyepiece of compound microscope is

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Real and diminished

Real and enlarged

Virtual and enlarged

Virtual and diminished

Young's modulus for steel is

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100

200

300

400

In which process, the change in internal energy of the system of zero:

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Isochoric process

isobaric process

Adiabatic process

Isothermal process

At every degree Celsius rise of temperature, the volume of a given mass of a gas at constant pressure increases by

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1/273 of its value at 0°C

1/373 of its value at 0°C

1/173 of its value of 0°C

1/700 of its value at 0°C

Is Boyle's law is applicable, to the isothermal process

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No

Yes

Some what applicable

None of these

In projectile motion, the acceleration in horizontal is

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Maximum

Minimum

Zero

None of these

The motion of a charged nucleus also produces a magnetic field which is

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Weaker than orbital electrons

Stronger than orbital electrons

Equal than orbital electrons

None of these

A church organ consist of open ended pipes ranging from 4m to 4 mm, if the speed ofsound is considered as 400 m/s then the min and max frequency is:

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400 Hz and 4 kHz

100 Hz and 100 kHz

50 Hz and 50kHz

400 Hz and 400 kHz

The optical fibre is covered for protection with

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rubber jacket

plastic jacket

steel jacket

copper jacket

The value of Faraday number is SI unit is

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9.65 Coulomb/kg/equivalent

9.65 x 10⁷Coulomb/kg/equivalent

9.65 x 10^-7Coulomb/kg/equivalent

9.65 Coulomb/kg/equivalent

An oil film floating on water surface show colours due to

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Interference

Diffraction

Scattering

Reflection

nuclear physics deals with

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Atom

Atomic nuclei

Elementary particles

Light

Human body pressure measure in

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torr

pascal

mmH_g

Nm^-2

The wave nature of light was proposed by

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Einstein

Maxwell

Huygen

Newton

The direction of velocity is along the direction of

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Motion

Displacement

Velocity

None of these

The direction of torque is

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The same as the direction of the corresponding applied force

Opposite to the direction of the applied force

Perpendicular to the direction of the applied force

Parallel to applied force

The SI units of acceleration is

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LT

LT^-1

LT^-2

L²T^-2

A substance which have empty conduction band is called

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Conductor

Insulator

Semiconductor

None of these

The vector sum of three vectors gives a zero resultant. What can be the orientations

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90^o

60^o

120^o

180^o

Which of the following cannot have an effect on the weight of an object?

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The distance of the object from a planet

The acceleration of the object

The placement of the object on a different planet

The mass of the object

Angle subtended at the centre of the circle by a body is called

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Angular velocity

Linear velocity

Angular displacement

All of these

The correct statement about poissons ratio is

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Its unit is N/m²

It is dimensionless

Its unit is Newton

Its dimensions MLT²

The expression for the range of the projectile is

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If the focal length of the eye piece 25.0 mm find its magnification

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12.0

14.0

- 11.0

- 13.0

Angular displacement generally expressed in

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Degrees

Revolution

Radian

All of these

The systolic pressure is

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120 torr

130 torr

150 torr

80 torr

According to the first condition of equilibrium, vector sum of all the forces action on the body must be

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maximum

minimum

zero

none of them

If v is the velocity of flow of liquid through a tube of area of cross-section A then according to equation of continuity

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v/A = constant

A/v = constant

Av = constant

None

In semiconductor Si or Ge a missing electron in covalent bond from an atom is a

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Charged atom

Hole

Ion

All of them

Force due to water flow is

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Ma/t

Mv/t

m/t

mt/v

The two forces of a couple do not follow the rule that

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They act on the same angle

They act in the opposite directions

They have same directions

They cancel out each other

In single slit diffraction the condition for second minimum is

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Sinθ = λ

d Sinθ =2λ

d Sinθ =3λ

d Cosθ =0

A force passing through the centre of gravity of a body

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Causes translation motion

Causes rotational motion

Produces no motion in the body

Produces both translational and rotational motion

At high altitude the blood flows out of nose and ear because

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The blood pressure increases at high altitudes

The percentage of oxygen in the air increases

The atmospheric pressure decreases there

The density of blood decreases at high altitudes

The dielectric constant K of an insulator cannot be.

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3

8

6

∞

The perpendicular distance from the axis of rotation to the line of the action of force is called

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Linear distance

Angular distance

Momentum arm

None of these

The light waves and radio waves differ in

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Speed

Frequency

Wavelength

Both B and C

Using a graded index fibres the time difference is reduced to about

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0.5 ns per km

1.0 ns per km

2.0 ns per km

2.3 ns per km

Molecules of a solid possess:

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Translation motion

Vibration motion

Rotation motion

Linear motion

A body is dropped from a tower reaches the earth surface in 4 sec where g is 10 m/s²the height of tower is

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80 m

20 m

160 m

40 m

Diffraction pattern has also been observed for:

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Proton

Neutron

Hydrogen atom

All of them

If a charged spherical conductor of radius 10 cm has potential V at a point distance 5 cm from its centre,then the potential at a point distance 15 cm from the centre will be

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1/3 V

2/3 V

3/2 V

3 V

The kinetic energy of a body becomes four times its initial value.The new linear momentum will be

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Four times the initial value

Thrice the initial value

Twice the initial value

Same as the initial value

The critical temperature of mercury is

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1.18 K

4.2 K

3.72 K

7.2 K

A spectrometer is used to find

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Wavelength of light

Refractive index of the prism

Angle of minimum deviation of prism

All of these

If a transverse wave has a speed of 10 m/ sec and frequency of 10 cycle/ sec itswavelength is:

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1 m

10^-2 cm

10 m

10 cm

The fusion of hydrogen into helium is more likely to take place:

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At high temperature and high pressure

At high temperature and low pressure

At low temperature and low pressure

At low temperature and high pressure

If an electron has an initial velocity in a direction different from that of an electric field the path of

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Straight line

Circle

Ellipse

Parabola

An ECG records the electric process in heart between

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Points on human skin

Two limbs of human foot

Two lungs of human

None of these

When the fuel ignited it turns to a gas at

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Low pressure

High pressure

Extremely high pressure

None of these

The rotational analogue of force is

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Torque

Momentum

Moment of inertia

None of these

The heart of machine is

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Lamp and camera unit

Aluminium drum

Charging unit

All of them

Velocity is a

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Scalar quantity

vector quantity

constant quantity

none of them

The amount of work done in bringing a unit positive charge from infinity to a point is called

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Potential

Potential difference

Absolute potential

None of these

The branch of physics which concerned with the ultimate particles of which the universe is composed is known as

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Solid state Physics

Particle Physics

Nuclear Physics

Atomic physics

A force of 0.01 N is exerted on a charge 1.2 x 10^-5C at a certain point The electric field at that point is

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1.2 x 10⁴N/C

8.3 x 10²N/C

8.3 x 10^-2N/C

There will be no change in _______ of light entering glass

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Velocity

Frequency

Direction

Wavelength

The drag force F on a sphere of radius 'r' moving slowly with speed V through a fluid of viscosity η by Stake's law

Choose an answer

F = πηra

F = 6πηrω

F = 6πηrV

F = 6πηraV

The conversion of electrical signals into light signals taken place due to

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Generator

Transmitter

Receiver

None of these

In which mode, the refractive index steps down form 1.52 to 1.48 at the boundary with the cladding?

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Single mode step index

multimode step index

multimode graded index

all of them

The study of nature has been classified into branches are:

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Two

Three

Four

None of these

The substances in which atoms cooperate with each other in such a way so as to exhibit a strong magnetic effect, are called

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diamagnetic substances

ferromagnetic substances

paramagnetic substances

all of them

The dimensions of force are

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[MLT^-1]

[M^oLT^-2]

[MLT^-2]

[ML⁰T^-2]

The amount of heat required to raise the temperature of one mole of a substance through

Choose an answer

1 C°

1 K

0 K°

None of these

Polaristion is a phenomenon associated with a certain type of wave.

Which condition must be fulfilled if the wave is to be polarised?

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It must be a longitudinal wave

It must be a light wave

It must be a transverse wave

The ratio of electro static force to the gravitational force between them is of the order of

Choose an answer

10³⁶

10³⁸

10⁴⁰

10⁴²

Why the toner is given a negative charge to the drum

Choose an answer

To spread over the drum

To stick the writing

To neutralize writing

None of these

The substances in which, atom are so oriented that their field support each other and the atoms behave like tiny magnets, are called

Choose an answer

diamagnetic substances

ferromagnetic substances

paramagnetic substances

all of them

The state of rest and state of motion are

Choose an answer

Irrelevant

Relative

Both

None of these

The efficiency of the diesel engine is

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25% to 35%

25% to 40%

35% to 40%

30% to 40%

The motion of a projectile is

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one dimension

two dimensions

three dimensions

four dimensions

The direction of the linear momentum is the direction of

Choose an answer

speed

velocity

weight

none of them

The uniformly accelerated equations are useful only for

Choose an answer

Angular motion

Curved motion

Linear motion

None of these

The body is in a state equilibrium when it is

Choose an answer

At rest

In motion

In rotation

None of these

The symbol K and G have been used to denote respectively:

Choose an answer

Young's modulus and bulk modulus

Young's modulus and shear modulus

Bulk modulus and shear modulus

Any of these

None of these

If the water falls from a dam into a turbine wheel 19.6 m below,then the velocity of water at the turbine is

(Take g = 9.8 m/s²)

Choose an answer

9.8 m/s

19.6 m/s

39.2 m/s

98.0 m/s

Hails fall faster than rain drops due to their

Choose an answer

Greater size

Greater mass

Greater area

None of these

When the direction of r and F are reverse

Choose an answer

the direction of torque remain unaltered

the magnitude of torque remain unchanged

both the magnitude and direction of torque remain unchanged

both the magnitude and direction of torque change

A material most suitable to make the permanent magnet are

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High retentivity

Large coercive current

Small domain friction

a and b

Direction of torque can be found out by

Choose an answer

head to tail rule

parallelogram rule

left hand rule

right hand rule

In an inertial frame of reference the weight of body equal to

Choose an answer

Force of attraction

Coulomb's force

Force of gravity

All of these

In Michelsons interference the movable mirror is moved and a shift of two fringes is observed then the distance moved by the mirror is

Choose an answer

λ/2

λ

2λ

None

The fringes produced in Young's double slit experiment will be wider if the distance between the two slits is

Choose an answer

small

large

zero

very large

The momentum of particle is numerically equal to its K.E What is the velocity of the particle

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9 ms^-1

3 ms^-1

2 ms^-1

1 ms^-1

Two bodies of masses m₁ and m₂ have equal momentum their kinetic energies E₁ and E₂ are in the ratio

Choose an answer

√m₁ : √m₂

m₁ : m₂

m₂ : m₁

m²₁ : m²₂

In slow Compression of a gas in a cylinder is reversible as the compression can be changed to expansion by

Choose an answer

Rapid decreasing the pressure

Slowly decreasing the pressure

Extremely decreasing the pressure

None of these

Angular acceleration is produced in a body by the physical quantity called

Choose an answer

momentum

vibration

torque

centrifugal force

Which of the following statements for an object in equilibrium not true?

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The object must be at rest

The object can be at rest

The object is moving at constant

The acceleration of the object is zero

The ratio of size of the image to the size of the object is called

Choose an answer

Resolving power

Magnification

Power

None of these

A body will be in rotational equilibrium if

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Unit of universal gas constant is SI is:

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W K^-1 mol^-1

J/Nk^-1 mol^-1

Jk^-1 mol^-1

erg K^-1 mol^-1

Assuming the earth as a sphere of radius 6400km the capacitance of earth is

Choose an answer

Infinite

Zero

771 μF

171 μF

When seen in green light the saffron and green portions of our National Flag will appear to be

Choose an answer

Black

Black and green respectively

Green

Green and yellow respectively

A body moving in a circular path with constant speed has

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Constant acceleration

Constant retardation

Variable acceleration

Variable speed and constant velocity

The approximate efficiency of electric motor is

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40 to 45%

49 to 56%

50 to 70%

50 - 93 %

Petrol engine converts heat energy to work roughly

Choose an answer

20%

25%

30%

40%

If the volume of a gas is to be increased four times then

Choose an answer

Its temperature must be doubled

At constant temperature its pressure must be decreased four times

At constant temperature its pressure must be increased two times

It cannot be increased

The relative permitivity ∈_r for transformer oil is

Choose an answer

2.9

3.0

2.1

2.4

Brownian motion confirms the truth of :

Choose an answer

Wave theory of light

Boyle's law

Kinetic theory of gases

Adiabatic process

Inverse square law for luminance is valid for

Choose an answer

Search light

Isotropic point source

Cylindrical source

All types of sources

Diffraction effect is

Choose an answer

More for a round edge

More for a sharp edge

Less for a sharp edge

None of these

A hole in a semi-conductor material is treated as

Choose an answer

positive charge

negative charge

neutral

none of them

Which effect provides direct experimental evidence that light is a transverse rather than a longitudinal wave motion?

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Light can be diffracted

Two coherent light waves can be made to interfere.

The intensity of light from a point source falls off inversely as the square of the distance from the source

Light can be polarized

Motion of rocket is based upon

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Newtons third law of motion

Law of conservation of momentum

Newtons law of gravitation

Both (a) and (b)

Equal vectors are said to be equal if by have

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Same magnitude and direction

Same magnitude and opposite

No position of initial points

Direction a and b

The cross product of two perpendicular vectors has magnitude

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Maximum value

Minimum value

Zero

None of these

In an inkjet printer, the toner drops are

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Charged

Not charged

Charged and deflected

None of these

In case of reflection of ray within a denser medium, angle of incidnet is ______ -angle of reflection

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Greater then

Smaller then

Equal to

None of these

In order to get interference using two light rays:

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The sources should be monochromatic and coherent

The sources should have the same frequency

Superposition should be linear

All of these

In young s interference experiment one slit is covered with a cellophane paper which absorbs half the intensity then

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No fringes are observed

All fringes will be darks

bright fringes will be less bright and dark will be less dark

Bright fringes will be brighter and dark fringes will be darks

In the formula for velocity of efflux v = √2gh, h is the

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Height of liquid column from bottom of vessel

Height of orifice from the bottom of the vessel

Height of liquid column above the orifice

Height of the vessel

The product of force times the perpendicular distance between some point and the line of action of the force is

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The moment of inertia action on it

The moment of force about the chosen point

The angular momentum of the body

None of these

If the acceleration due to gravity is 10 ms^-2 and the units of length and time are changed to kilometer and hour respectively,the numerical value of acceleration is

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360000

72000

36000

129600

The approximate efficiency of steam locomotive is

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8%

9%

10%

11%

The substances which break just after the elastic limit is reached, are known as

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brittle substances

ductile substances

plastic substances

elastic substances

In metallic crystals which of the following thing remains constant?

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amplitude of oscillations

temperature of solid

average atomic positions

all of them

At high speed and for long trajectories the air friction is

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Negligible

Equal to gravity

More than gravity

None of these

The total change in momentum of the isolated two ball system is

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Maximum

Minimum

Zero

None of these

The modulus of rigidity of a liquid is:

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Zero

1

Infinite

None of these

'S' is the arc length and after one revolution it becomes

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2π

2π/r

2πr

None of these