The masses of three wires of copper are in the ratio 1:3:5 and lengths are in the ratio 5:3:1. Then the ratio of their electrical resistance are
Options
(a) (1:3:5) (b) (5:3:1) (c) (1:15:25) […]
Rutherford’s α-scattering experiment concludes that
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(a) there is a heavy mass at centre (b) electrons are revolving around the nucleus (c) both (a) and (b) (d) None of these
Correct Answer:
there […]
Mass defect is known as
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(a) ionisation energy (b) binding energy (c) packing fraction (d) activity
Correct Answer:
binding energy
Explanation:
No explanation available. Be the first to write the explanation for […]
An electric lamp is connected to 220 V, 50 Hz supply. Then the peak voltge is
Options
(a) 210 V (b) 211 V (c) 311 V (d) 320 V
Correct Answer:
311 V
In the series resonance the value of impedence is 3 Ω and the resistance is 4Ω, then the value of power factor of the circuit is
Options
(a) (4/3) (b) (3/4) (c) zero […]
A cricket ball of mass 250 g collides with a bat with velocity 10 m/s and returns with same velocity within 0.01 seconds. The force acted on bat is
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(a) 25 N […]
The length of second pendulum is 1 m on earth. If mass and diameter of the planet is double than that of earth, then length becomes
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(a) 1 m (b) 2 m […]
A hollow metal sphere of radius 10 cm is charged such that the potential on its surface is 80V. The potential at the centre of the sphere is
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(a) zero (b) 80 […]
A wire is suspended vertically from one of its ends is stretched by attaching a weight of 200 N to the lower end. The weight stretches the wire by 1 mm. Then the elastic energy […]
If a carnot engine is working with source temperature at 227⁰C and sink temperature at 27⁰C, its efficiency will be
Options
(a) 40% (b) 10% (c) 67% (d) 50%
Correct Answer:
40%
Explanation: […]
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