Two resistances 3Ω and 6Ω are connected in parallel and a 4Ω resistance is connected in series. The current through 3Ω resistance is 0.8 A. Then the potential drop through 4Ω resistance is
Options […]
An α-particle and a proton are accelerated through same potential difference from rest. Find the ratio of their final velocity
Options
(a) (4:1) (b) (1:1) (c) (1:√2) (d) (1:2)
Correct Answer:
(1:√2)
Explanation:
When […]
When a Daniel cell is connected in the secondary circuit of a potentiometer, the balancing length is found to be 540 cm. If the balancing length becomes 500 cm when the cell is short circuited […]
The drift velocity of the electrons in a copper wire of length 2 m under the application of a potential difference of 200 V is 0.5 ms⁻¹. Their mobility is (in m² V⁻¹ s⁻¹)
The identical cells connected in series are needed to heat a wire of length one meter and radius ‘r’ by 10⁰C in time ‘t’. How many cells will be required to heat the wire of […]
Charge passing through a conductor of cross-section area A=0.3 m² is given by q=3t²+5t+2 in coulomb, where t is in second. What is the value of drift velocity at t= 2 s?(Given, n=2×10²⁵/m³)
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A wire of a certain material is stretched slowly by ten percent. Its new resistance and specific resistance become respectively
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(a) both remain the same (b) 1.1 times, 1.1 times (c) 1.2 times, […]
A wire of resistance 4 ohm is stretched to twice its original length. The resistance of stretched wire would be
Options
(a) 4Ω (b) 8Ω (c) 16Ω (d) 2Ω
Correct Answer:
16Ω
Explanation:
Resistance […]
A voltmeter of range 2 V and resistance 300Ω cannot be converted into ammeter of range
Options
(a) 1A (b) 1mA (c) 100mA (d) 10mA
Correct Answer:
1mA
Explanation:
Ig = (2 / […]
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) […]
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