All components of the electromagnetic spectrum in vacuum have the same
Options
(a) Energy (b) Velocity (c) Wavelength (d) Frequency
Correct Answer:
Velocity
Explanation:
No explanation available. Be the first to write the […]
The minimum wavelength of X-rays emitted by X-ray tube is 0.4125 Å. The accelerating voltage is
Options
(a) 30 kV (b) 50 kV (c) 80 kV (d) 60 kV
Correct Answer:
30 kV
A radiotransmitter radiates 1 kW power at a wavelength 198.6 m. How many photons does it emit per second
Options
(a) 10¹⁰ (b) 10²⁰ (c) 10³⁰ (d) 10⁴⁰
Correct Answer:
10³⁰
Explanation:
No […]
Sodium and copper have work function 2.3 eV and 4.5 eV respectively. The ratio of their threshold wavelengths is nearest to
Options
(a) 1 : 2 (b) 4 : 1 (c) 2 : […]
A 1 µA beam of protons with a cross-sectional area of 0.5 sq.mm is moving with a velocity of 3 x 10⁴ m/s. The charge density of beam is
Options
(a) 6.6 x […]
The de-Broglie wavelength of a proton(charge = 1.6 x 10⁻¹⁹ C, Mass = 1.6 x 10⁻²⁷ kg) accelerated through a potential difference of 1 kV is
Options
(a) 600 Å (b) 0.9 x […]
The potential difference applied to an X-ray tube is 5 kV and the current through it is 3.2 mA. The number of electrons striking the target per second is
Options
(a) 5 x 10¹⁶ […]
The de-Broglie wavelength of an electron having 80 eV of energy is nearly(Given 1 ev= 1.6 x 10⁻¹⁹ kg, Mass of electron=9 x 10⁻³¹ kg, Planck’s constant= 6.6 x 10⁻³⁴ J-sec)
Options
(a) […]
A light whose frequency is equal to 6.0 x 10¹⁴ Hz is incident on a metal whose work function is 2 eV. (h= 6.63 x 10⁻³⁴ Js, 1 ev = 1.6 x 10⁻¹⁹ J). The […]
The shortest wavelength in Lyman series is 91.2 nm. The largest wavelength of the series is
Options
(a) 121.6 nm (b) 182.4 nm (c) 243.4 nm (d) 364.8 nm
Correct Answer:
121.6 nm
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