The number of photons of wavelength of 540 nm emitted per second by an electric bulb of power 100 W is (given h=6×10⁻³⁴ J-s)
Options
(a) 100 (b) 1000 (c) 3×10²⁰ (d) 3×10¹⁸
Correct […]
Maximum velocity of the photoelectron emitted by a metal is 1.8×10⁶ ms⁻¹. Take the value of specific charge of the electron is 1.8×10¹¹ C kg⁻¹. Then the stopping potential in volt is
Options
The additional energy that should be given to an electron to reduce its de-Broglie wavelength from 1nm to 0.5nm is
Options
(a) 2 times the initial kinetic energy (b) 3 times the initial […]
The Davisson- Germer experiment is the direct evidence of
Options
(a) particle nature of electrons (b) wave nature of electrons (c) wave nature of light (d) particle nature of light
Correct Answer:
wave […]
Photons of 5.5 eV energy fall on the surface of the metal emitting photoelectrons on maximum kinetic energy 4.0eV. The stopping voltage required for these electrons is
Options
(a) 4.0 V (b) 5.5 […]
The speed of an electron having a wavelength of 10⁻¹⁰ m is
Options
(a) 6.26×10⁶ m/s (b) 5.25 x10⁶ m/s (c) 7.25×10⁶ m/s (d) 4.24×10⁶ m/s
Correct Answer:
7.25×10⁶ m/s
Explanation:
λ = h […]
Einstein’s photoelectric equation is
Options
(a) Emax=hν-φ (b) E=mc² (c) E²=p²c²+m₀²c⁴ (d) E=(1/2)mv²
Correct Answer:
Emax=hν-φ
Explanation:
No explanation available. Be the first to write the explanation for this question by commenting […]
The threshold wavelength for photoelectric effect of a metal is 6500 Å. The work function of the metal is approximately
Options
(a) 0.1 eV (b) 1 eV (c) 2 eV (d) 3 eV
The de-Broglie wavelength of an electron is the same as that of a 50 KeV X-ray photon. The ratio of the energy of the photon to the kinetic energy of the electron is (the energy […]
If the wavelength of incident light falling on a photosensitive material decreases, then
Options
(a) photoelectric current increases (b) stopping potential decreases (c) stopping potential remains constant (d) stopping potential increases
Correct Answer: […]
2017 Copyright Doctor Dreams Training Academy