The wave theory of light does not explain photoelectricity because
light waves carry little energy
particles cannot be emitted by waves
the frequency of light waves too high
there is a threshold wavelength for electron emission
the wavelength of Light waves is too short
Correct answer is A
The amplitude of oscillation of a simple pendulum bob diminishes slowly because
energy is applied by some external agencies
frictional forces dissipate the energy of motion
the frequency of oscillation increases with the mass of the bob
the frequency of oscillation varies with time
the period of oscillation varies with time.
Correct answer is D
The amplitude and the frequency of an oscillating pendulum decrease gradually with time.
I only
II only
III only
I and II only
I, II and III
Correct answer is C
The quality or timbre of sound is that characteristic which enables us to distinguish one sound from another having the same pitch and loudness.
The motion of the wheel of a bicycle moving on a smooth straight road is
oscillatory and random
oscillatory and translational
rotational and oscillatory
rotational and random
rotational and translational
Correct answer is E
No explanation has been provided for this answer.
Which of the following is NOT a component of a slide projector?
Concave mirror
Condenser
Convex mirror
light source
Screen
Correct answer is A
You will find convex lenses in telescopes, microscopes, magnifying glasses, cameras, slide and movie projectors, and other instruments that use light to create an image