In the given figure net magnetic field at O will be

|
(a) |
(b) |
(c) |
(d) |
In the given figure net magnetic field at O will be

|
(a) |
(b) |
(c) |
(d) |
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As shown in the figure, a magnet is moved with a fast speed towards a coil at rest. Due to this induced electromotive force, induced current and induced charge in the coil is E, I and Q respectively. If the speed of the magnet is doubled, the incorrect statement is

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(a) E increases |
(b) I increases |
(c) Q remains same |
(d) Q increases |

A long copper tube of inner radius R carries a current i. The magnetic field B inside the tube is
|
(a) |
(b) |
(c) |
(d) Zero |
Three resistors each of 2 ohm are connected together in a triangular shape. The resistance between any two vertices will be
|
(a) 4/3 ohm |
(b) 3/4 ohm |
(c) 3 ohm |
(d) 6 ohm |
A thin lens made of glass of refractive index m = 1.5 has a focal length equal to 12 cm in air. It is now immersed in water Its new focal length is
|
(a) 48 cm |
(b) 36 cm |
(c) 24 cm |
(d) 12 cm |
Assertion : In meter bridge experiment, a high resistance is always connected in series with a galvanometer.
Reason : As resistance increases current through the circuit increases.
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(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
|
(b) If both assertion and reason are true but reason is not the correct explanation of the assertion. |
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(c) If assertion is true but reason is false. |
|
(d) If the assertion and reason both are false. |