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Planck’s constant is given by

(a) slope of the line
(b) product of the slope of the line and charge on electron
(c) intercept along y-axis divided by charge on the electron
(d) product of the intercept along x-axis and mass of the electron
5 The energy of photon of wavelength 450 nm is
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(a) 2.5 × 10 J
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(b) 1.25 × 10 J
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(c) 4.4 × 10 J
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(d) 2.5 × 10 J
6 The slope of the stopping potential versus ‘ frequency graph for photoelectric effect is equal
to

(a) h
(b) he
(c) h/e
(d) e
7 Work function of three metals A, B and C are 4.5 eV, 4.3 eV and 3.5 eV respectively. If a light
of wavelength 4000 Å is incident on the metals then
(a) photoelectrons are emitted from A.
(b) photoelectrons are emitted from B.
(c) photoelectrons are emitted from C.
(d) photoelectrons are emitted from all the metals.
8 According to Einstein’s photoelectric equation the plot of the kinetic energy of the emitted
photo-electrons from a metal vs the frequency of the incident radiation gives a straight line
whose slope
(a) depends on the nature of the metal used.
(b) depends on the intensity of the radiation.
(c) depends both on the intensity of the radiation and the metal used.