In the phenomenon of electric discharge through gases at low pressure, the coloured glow in the tube appears as a result of
Options
(a) Collisions between the charged paricles emitted from the cathode […]
A particle of mass 1mg has the same wavelength as an electron moving with a velocity of 3 x 10⁶ ms⁻¹. The velocity of the particle is: (mass of electron = 9.1 x 10⁻³¹ kg) […]
A wire of a certain material is stretched slowly by ten percent. Its new resistance and specific resistance become respectively
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(a) both remain the same (b) 1.1 times, 1.1 times (c) 1.2 times, […]
The ratio of minimum wavelengths of Lyman and Balmer series will be
Options
(a) 5 (b) 10 (c) 1.25 (d) 0.25
Correct Answer:
0.25
Explanation:
Minimum wavelength is for higher energy n = 1 […]
Two nuclei have their mass numbers into the ratio of 1:3. The ratio of their nucleus densities would be
Options
(a) 1 : 3 (b) 3 : 1 (c) (3)¹/³ : 1 (d) […]
If M (A; Z), Mₚ and Mₙ denote the masses of the nucleus AZ X, proton and neutron respectively in units of u (1u = 931.5 MeV/c) and BE represents its bonding energy in MeV, […]
In an a.c circuit the e.m.f. (e) and the current (i) at any instant are given respectively by e = E₀ sin ?t i = I₀ sin (?t – ?) The average power in the […]
The distance travelled by a particle starting from rest and moving with an acceleration 4/3 ms⁻², in the third second is
Options
(a) 10/3 m (b) 19/3 m (c) 6 m (d) 4 m
A roller coaster is designed such that riders experience “weightlessness” as they go round the top of a hill whose radius of curvature is 20 m. The speed of the car at the top of […]
A particle of mass 1 mg has the same wavelength as an electron moving with a velocity of 3 x 10⁶ ms⁻¹. The velocity of the particle is
Options
(a) 3 x 10⁻³¹ […]
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