dual nature of matter and radiation

Photoelectric current is ………. proportional to the number of photoelectrons emitted per second.

• inversely

• directly

• first directly and then inversely

• none of these

The stopping potential depends upon the ....……….. of the fastest electron.

• velocity

• charge

• mass

• density

For a given frequency of the incident radiation, the stopping potential …..…….... of its intensity.

• is directly proportional

• is inversely proportional

• is independent

• None of these

The maximum kinetic energy of the photoelectrons is ….......... proportional to the frequency of incident radiation.

• inversely

• directly

• first directly and then inversely

• none of these

In the photoelectric effect, if the intensity of incident light increases, the

• K.E. of emitted electrons decreases

• K.E. of emitted electrons increases

• photo electric current increases

• photo electric current decreases.

The stopping voltage in photoelectric effet depends

• only on the frequency of incident photon

• only on the intensity of the incident light

• only on the nature of the surface of metal

• on the frequency of incident light and the nature of the metal

The maximum kinetic energy of photo electrons varies with the frequency of the incident radiation as

• 
• 
• 
• 

Protons and alpha particles have the same de-Broglie wavelength. What is same for both of them ?

• (a) Energy

• (b) Time period

• (c) Frequency

• (d) Momentum

Kinetic energy of emitted electrons depends upon :

• (a) frequency

• (b) intensity

• (c) nature of atmosphere surrounding the electrons

• (d) none of these

De-Broglie wavelength of a body of mass m and kinetic energy E is given by (symbols have their usual meanings):

• (a) h/√2mE
  

• (b) h/2mE

• (c)√ 2mE/h

• (d) h/mE