Large transformers, when used for some time, become hot and are cooled by circulating oil. The heating of transformer is due to
Options
(a) Both the hysterisis loss and heating effect of current […]
Penetrating power of X-rays does not depend on
Options
(a) potential difference (between anode and cathode) (b) Current in the filament (c) Wavelength ( of X-rays) (d) Energy ( of X-rays)
Correct Answer: […]
Photons of energy 6 eV are incident on a metal surface whose work function is 4 eV. The minimum kinetic energy of the emitted photo-electrons will be
Options
(a) 0 eV (b) 1 eV […]
The sodium nucleus ₁₁Na²³ contains
Options
(a) 11 electrons (b) 12 protons (c) 23 protons (d) 12 neutrons
Correct Answer:
12 neutrons
Explanation:
No explanation available. Be the first to write the explanation […]
For principal quantum number n=3, the possible values of orbital quantum number l are
Options
(a) 1,2,3 (b) 0,1,2,3 (c) 0,1,2 (d) (-1,0,+1)
Correct Answer:
0,1,2
Explanation:
No explanation available. Be the first […]
A solenoid of length l metre has self inductance L henry. If number of turns are doubled, its self inductance
Options
(a) Becomes 2 L henry (b) Becomes 4 L henry (c) Remains […]
The velocity v of waves produced in water depends on their wavelength λ, the density of water d and acceleration due to gravity g. These quantities are related as (where K is a dimensionless constant) […]
If critical angle for a material to air passage is 30°, the refractive index of the material will be
Options
(a) 1 (b) 1.5 (c) 2 (d) 2.5
Correct Answer:
2
Explanation:
No […]
1 a.m.u. is equivalent to
Options
(a) 1.6×10⁻¹² J (b) 1.6×10⁻¹⁹ J (c) 1.5×10⁻¹⁰ J (d) 1.5×10⁻¹⁹ J
Correct Answer:
1.5×10⁻¹⁰ J
Explanation:
No explanation available. Be the first to write the explanation […]
From a disc of radius R, a concentric circular portion of radius r is cut-out so as to leave an annular disc of mass M. The moment of inertial of this annular disc about the […]
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