The escape velocity of a body from earth’s surface is Ve. The escape velocity of the same body from a height equal to 7R from earth’s surface will be
Options
(a) Ve/√2 (b) […]
A satellite in a circular orbit of radius R has a period of 4 hours. Another satellite with orbital radius 3R around the same planet will have a period (in hours)
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(a) […]
A cylindrical capacitors has charge Q and length L. If both the charge and length of the capacitors are doubled, by keeping other parameters fixed, the energy stored in the capacitor
Options
(a) […]
A capacitor having a capacity of 2 μF is charged to 200V and then the plates of the capacitor are connected to a resistance wire. The heat produced in joule will be
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A tuned amplifier circuit is used to generate a carrier frequency of 2 MHz for the amplitude modulation. The value of √LC is
Options
(a) 1/2πx10⁶ (b) 1/2×10⁶ (c) 1/3πx10⁶ (d) 1/4πx10⁶
Correct […]
A common emitter amplifier is designed with n-p-n transistor (α=0.99). The input impedence is 1kΩ and load is 10kΩ. The voltage gain will be
Options
(a) 9900 (b) 99 (c) 9.9 (d) 990
Correct […]
A horizontal straight conductor kept in north-south direction falls under gravity. Then
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(a) No e.m.f. is induced along the length of conductor (b) A current will be induced from south to north […]
A coil of N turns and mean cross-sectional area A is rotating with uniform angular speed ω about an axis at right angle to uniform magnetic field B. The induced e.m.f. E in the coil […]
Electrons in a certain energy level n=n₁, can emit 3 spectral lines. When they are in another energy level, n=n₂. They can emit 6 spectral lines. The orbital speed of the electrons in the two […]
In a laser tube, all the photons
Options
(a) have same energy (b) have same wavelength (c) move in same direction (d) move with same speed
Correct Answer:
move with same speed
Explanation: […]
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