Home
Class 12
PHYSICS
In a photoelectric effect, electrons are...

In a photoelectric effect, electrons are emitted

A

with a maximum velocity proportional to the frequency of the incident radiation

B

at a rate that is independent of the intensity of the incident radiation

C

only if the frequency of the incident radiation is above a certain threshold value

D

only if the temperature of the emitter is high

Text Solution

Verified by Experts

The correct Answer is:
C
`KE_(max)=hv-phi`
`implies(1)/(2)mv_(max)^(2)=hv-phi`
`impliesv_(max)=sqrt((2(hv-phi)/(m)))`
Hence, (a) is incorrect.
Since `n=((IA)/(hv))`, therefore rate of emission of electrons is proportional to the intensity (I).
`KE_(max)=hv-phi`
Hence,(c ) is true.
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • PHOTOELECTRIC EFFECT

    CENGAGE PHYSICS|Exercise Multiple Correct|10 Videos

  • PHOTOELECTRIC EFFECT

    CENGAGE PHYSICS|Exercise Linked Comprehension|44 Videos

  • PHOTOELECTRIC EFFECT

    CENGAGE PHYSICS|Exercise Subjective|16 Videos

  • NUCLEI

    CENGAGE PHYSICS|Exercise QUESTION BANK|59 Videos

  • RAY OPTICS

    CENGAGE PHYSICS|Exercise DPP 1.6|12 Videos

Similar Questions

Explore conceptually related problems

In the photoeletric effect, electrons are emitted

In photoelectric effect, the number of emitted photoelectrons is proportional to _____ of incident light.

Knowledge Check

  • In photoelectric effect,

    A
    the emission of electron is the result of elastic collision between the incident photon and the electron.
    B
    absorption of photon is a gradual process.
    C
    the emission of electron is a result of inelastic collision between the photon and the electron.
    D
    at the threshold frequency, the kinetic energy of ejected electrons is maximum.

  • In photoelectric effect,

    A
    In photoelectric current is directly proportional to the intensity of incident light.
    B
    `K.E._(max)` of ejected electrons is dependent on intensity of radiations.
    C
    there is no time lag between the incidence of photons and ejection of electrons
    D
    All of these are correct.

  • In photoelectric effect

    A
    photons come out of a metal when it is hit by a beam of electrons
    B
    photons come out of the nucleus of an atom under the action of an electric field
    C
    electrons come out of a metal with a constant velocity which depends on the frequency and intensity of incident radiation
    D
    electrons come out of a metal with different velocities nor greater than a certain value which depends only on the frequency of the incident light and not on its intensity

    • Similar Questions

    Explore conceptually related problems

    In photoelectric effect

    In photoelectric effect, emitted electrons are

    Assertion: In both radio actiivity and photoelectric effect electrons may be ejected. Reason: In photoelectric effect and radio activity emission occurs only of unstable elements.

    In a photoelectric effect , the K.E. of electrons emitted from the metal surface depends upon

    In a photoelectric effect experiment, for radiation with frequency v_0 with hv_0 = 8eV, electrons are emitted with energy 2 eV. What is the energy of the electrons emitted for incoming radiation of frequency 1.25 v_0 ?

    Home
    Profile