Monochromatic light of frequency 6.0 x 10¹⁴ Hz is produced by a laser. The power emitted is 2 x 10⁻³ ?. The number of photons emitted, on the average, by the sources per second is […]
A 5 watt source emits monochromatic light of wavelength 5000Å. When placed 0.5 m away, it liberates photoelectrons from a photosensitive metallic surface. When the source is moved to a distance of 1.. m, the […]
A steady current of 1.5 amp flows through a copper voltmeter for 10 minutes. If the electrochemical equivalent of copper is 30 x 10⁻⁵ g coulomb⁻¹, the mass of copper deposited on the electrode will […]
The resistance of an ammeter is 13Ω and its scale is graduated for a current upto 100 amps. After an additional shunt has been connected to this ammeter it becomes possible to measure currents upto […]
Three resistances P,Q,R each of 2Ω and an unknown resistances S form the four arms of a Wheatstone bridge circuit. When a resistance of 6Ω is connected in parallel to S the bridge gets balanced. […]
If the nucleus ²⁷₁₃Al has nuclear radius of about 3.6 fm, then ¹²⁵₃₂Te would have its radius approximately as
Options
(a) 9.6 fm (b) 12.0 fm (c) 4.8 fm (d) 6.0 fm
Correct Answer: […]
The total energy of electron in the ground state of hydrogen atom is -13.6 eV. The kinetic energy of an electron in the first excited state is
Options
(a) 6.8 eV (b) 13.6 […]
What is the value of incidence L for which the current is maximum in a series LCR circuit with C = 10 µF and ? = 1000 s⁻¹?
Options
(a) 1 mH (b) […]
A transformer is used to light a 100 W and 110 V lamp from a 220 V mains. If the main current is 0.5 amp, the efficiency of the transformer is approximately
Options
The primary and secondary coil of the transformer have 50 and 1500 turns respectively. If the magnetic flux ? linked with the primary coil is given by ? = ?￢ﾂﾀ + 4t, where ? is […]
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