CBSE
Multiple Choice QuestionsFlash light equipped with a new set of batteries, produces bright white light. As the batteries wear out
the light intensity gets reduced with no change in its colour
light colour changes first to yellow and then red with no change in intensity
it stops working suddenly while giving white light
colour changes to red and also intensity gets reduced
The kinetic energy of an electron, which is accelerated in the potential difference of 100 V, is
1.6 × 10-17 J
1.6 × 10-14 J
1.6 × 10-10 J
1.6 × 10-8 J
Light of frequency v falls on material of threshold frequency vo, Maximum kinetic energy of emitted electron is proportional to
ν - νo
ν
vo
The work function for metals A, Band C are respectively 1.92 eV, 2.0 eV and 5 eV. According to Einstein's equation the metals which will emit photo, electrons for a radiation of wavelength 4100 Ao is/are
none
A only
A and B only
All the three metals
If alpha, beta and gamma rays carry same momentum, which has the longest wavelength?
Alpha rays
Beta rays
Gamma rays
None all have same wavelength
Light travels faster in air than that in glass. This is accordance with
wave theory of light
corpuscular theory of light
neigther (a) nor (b)
Both (a) and (b)
Relation between wavelength of photon and electron of same energy is
λph > λe
λph < λe
λph = λe
= constant
Which one of the following graph represents the variation of maximum kinetic energy (Ek) of the emitted electrons with frequency v in photoelectric effect correctly?
If the sun rays are incidenting at 60° angle and intensity is I. If the sun rays are made incident at 30° angle, then what will be the intensity?
3 l
A vessel of height 2 d is half filled with a liquid of refractive index and the other half with a liquid of refractive index n (the given liquids are immiscible). Then, the apparent depth of the inner surface of the bottom of the vessel (neglecting the thickness of the bottom of the vessel) will be
