The pitch of a sound is most closely related to its:
Wave form
Period
Amplitude
Frequency
The speed of sound in air at 21 °C is:
336ms-1
343ms-1
430ms-1
470ms-1
In case of OR and AND operation, if switches s1 and s2 both are open then lamp is:
On
Off
Sometimes on and sometimes off
Neither on nor off
1 bel=
0.1 dB
10 dB
100 dB
0.01 dB
The frequency of silent whistle is:
20,000 Hz – 25000Hz
2000 Hz – 2500Hz
200 KHz – 2000 Hz
25000 KHz
The unit of intensity of sound:
Wm-1
Wm-2
Wm
Wm2
The intensity of lawn mover is:
10-1 wm-2
10-2 wm-2
10-3 wm-2
10-4 wm-2
Which frequency is used by elephants to communicate with each other:
Zero frequency
Low frequency
Medium frequency
High frequency
