Physics ECAT Pre Engineering Online Test With Answers

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Physics ECAT Pre Engineering Online Test

Sr. # Questions Answers Choice
1 The power factor of resonant series circuit is 1 0 -1 0.5
2 In RLC series circuit, resonance occurs when X<sub>L &gt; Xc</sub> X<sub>L &lt; Xc</sub> X<sub>L = Xc</sub> None of these
3 A resonance curve for RLC series circuit is a plot of frequency versus Voltage Current Impedance Reactance
4 The r.m.s. value of alternating current is equal to its maximum value at angle of 60<span style="color: rgb(84, 84, 84); font-family: arial, sans-serif; font-size: small;">°</span> 45<span style="color: rgb(84, 84, 84); font-family: arial, sans-serif; font-size: small;">°</span> 30<span style="color: rgb(84, 84, 84); font-family: arial, sans-serif; font-size: small;">°</span> 90<span style="color: rgb(84, 84, 84); font-family: arial, sans-serif; font-size: small;">°</span>
5 The device which allows only the flow of an A.C. through a circuit is Capacitor Inductor D.C. motor Battery
6 Alternating current can induce voltage because it has a High peak value Varying magnetic field Stronger field than direct curren Constant magnetic field
7 An A.C varies as a function of Current Voltage Time Charge
8 At higher frequency of the alternating current, the capacitive reactance Xc Increases Decreases Remains the same Increases only when the voltage increases
9 Which one of the following is correct? V<sub>o</sub>= 1.414 V<sub>rms</sub> I<sub>ams</sub>= 1.414 I<sub>o</sub> VO = 10.70 Vrms Both a and b
10 In an A.C circuit with resistor only, the current and voltage have a phase angle of 90<span style="color: rgb(84, 84, 84); font-family: arial, sans-serif; font-size: small;">°</span> 0<span style="color: rgb(84, 84, 84); font-family: arial, sans-serif; font-size: small;">°</span> 180<span style="color: rgb(84, 84, 84); font-family: arial, sans-serif; font-size: small;">°</span> none of these
11 The basic circuit elements of A.C circuit are Resistor Inductor Capacitor All the three
12 During each cycle, alternating voltage reaches a peak value One time Two times Four times A number of times depending on the frequency
13 The average of A.C. current and voltage over a complete cycle is Maximum zero Neither zero nor maximum None of these
14 Carnot heat engine only used isothermal processes adiabatic processes both of them none of them
15 Sadi carnot described an ideal heat engine in 1820 1840 1860 1880
16 We cannot utilize the heat contents of oceans and atmosphere because there is no reservoir at the same temperature there is no reservoir at the temperature lower than any one of two there is no reservoir at the temperature higher than any one of two none of them
17 For the working of a heat engine, there must be a source of heat at high temperature a sink at low temperature both of them none of them
18 According to the second law, which is must to produce work a source contains a large amount of heat energy two sources at the same temperature two sources at the different temperatures a source contains a small amount of energy
19 It is impossible to devise a processes which may convert heat, extracted from a single reservoir, entirely into work without leaving any change in the working system. This is the statement of Clausius statement of second law Kelvin'sstatement of second law Clausius statement of first law Kelvin's statement of first law
20 The percentage of available heat energy converted into work by a diesel engine is roughly 35 %` 40 % 35 - 40 % 25 %
21 The percentage of available heat energy converted into work by a petrol engine is roughly 35 % 40 % 35 to 40 % 25 %
22 The second law of thermodynamics is concerned with the circumstances in which heat can be converted into work direction of flow of heat none of them both of them
23 First law of thermodynamics tells us that heat energy can be converted into equivalent amount of work, but it is silent about how heat is absorbed how heat extracted how this conversion takes place none of them
24 In a heat engine, heat is supplied by the cold reservoir sink hot reservoir none of them
25 The earliest heat engine was petrol engine diesel engine electric engine steam engine
26 A heat engine is that which converts mechanical energy into thermal energy thermal energy into mechanical energy K.E into potential energy heat energy into light energy
27 The example of irreversible process is slowly liquification slowly evaporation an explosion all of them
28 The example of reversible process is an explosion changes occur suddenly slow compression of a gas all of them
29 If a process cannot be retraced in the backward direction by reversing the controlling factors, it is a reversible process an irreversible process any one of them both of them
30 A reversible cycle is the one in which some of the changes are reversible all of the changes are reversible all of the changes are irreversible none of them
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