A simple pendulum has a metal bob which is negatively charged.If it is allowed to oscillate above a positively charged metallic plate then its time period will
increase
decrease
remain the same
become zero
An object moving at a speed greater than that of sound is said to be moving at:
ultrasonic speed
sonic speed
infrasonic speed
supersonic speed
Delhi Radio Station transmits musical programmes at 219 m wavelength and 1300 Hz frequency.Calculate the velocity of radio waves.
2.847 x 10-5
3.148 x 105
2.847 x 105
3.84 x 10-5
A sitar player plucks the wire of a sitar.After a short time each part of the wire starts vibrating in a direction perpendicular to the wire.Is the propogation of this disturbance a longitudinal or a transverse wave?
Longitudinal
Transverse
Stationary
Both longitudinal and transvers
The speed of the bob of an oscillating pendulum is zero
at the mean position
at an extreme position
between the mean position and the left extreme
between the mean position and the right extreme
Find the time period of a wave whose frequency is 400 MHz?
0.0012 s
0.0025 s
0.0015 s
0.0010 s
A boat at anchor is rocked by waves whose troughs are 150 m apart and whose velocity is 30 m/s.How often do the crests reach the boat ?
0.2 s
10 s
0.5 s
5 s
S.I unit of wave length (λ) is
centimetre
millimetre
killometre
metre
Longitudinal waves cannot travel through
vacuum
solids
liquids
gases
In SONAR we use
ultrasonic waves
infrasonic waves
radio waves
audible sound waves
