A metal rod of length l cuts across a uniform magnetic field B with a velocity v. If the resistance of the circuit of which the rod forms a part is r, then the force […]
Two charged particles have charges and masses in the ratio 2:3 and 1:4 respectively. If they enter a uniform magnetic field and move with the same velocity, then the ratio of their respective time periods […]
Radii of curvature of a converging lens are in the ratio 1:2. Its focal length is 6 cm and refractive index is 1.5. Then, its radii of curvature are ………… respectively
Options
(a) […]
When we close one slit in the young’s double slit experiment, then
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(a) the bandwidth increased (b) the bandwidth is decreased (c) the interference pattern is shifted (d) the diffraction pattern is observed
A soap bubble is charged to a potential 12V. If its radius is doubled, then the potential of the bubble becomes
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(a) 12V (b) 24V (c) 3V (d) 6V
Correct Answer:
6V
The force of repulsion between two electrons at a certain distance is F. The force between two protons separated by the same distance is (mp=1836mₑ)
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(a) 2F (b) F (c) 1836F (d) […]
The output of an AND gate is connected to both the inputs of a NOR gate, then this circuit will acts as a
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(a) NOR gate (b) AND gate (c) NOT gate […]
If the feedback voltage is increased in a negative feedback amplifier, then
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(a) both gain and distortion decrease (b) the distortion increase (c) the gain decrease and distortion increase (d) the gain […]
In p- type semiconductor, the acceptor level lies
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(a) near the conduction band (b) halfway between conduction and valence band (c) within conduction band (d) near the valence band
Correct Answer:
near […]
In a ionised gas,the mobile charge carriers are
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(a) electrons (b) both positive ad negative ions (c) electrons and positively charged ions (d) positive ions only
Correct Answer:
electrons and positively charged […]
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