Question

19) (A): In photoelectric effect, when the frequency of incident light is doubled,
kinetic energy is more than doubled
(R) : Photo current increases when the intensity of incident light is
and is independent of frequency
a) Both A and R are true and R is the correct explanation
b) Both A and R are true but R is not the correct explanation of A
c) A is true but R is false
d) A is false but R is true
20) Energy of a photon with a wavelength of 450nm is
a) 4.36x10-12 ergs
b) 4.36x10-13 ergs
c) 4.36x10-20 ergs
d) 4.36x10-11 ergs
21) A wave has a frequency of 3x10power15 sec . The energy of that photon is

a) 1.6x10-12 erg ) 3.2x10-11erg c) 2.0x10-11erg d) 3x10power 15 erg
22) The wavelength of light having wave number 4000cm-1 is
d) 25nm
b) 250 um
c) 25 meu(u)m
a) 2.5 um​

Answer 1

Answer:

19. d)A is false but R is true.

20. a) 4.36x10-12 ergs.

21 . c) 2.0x10-11erg.

22. a) 2.5 um