- AParallel to each other
- BAntiparallel to each other
- CPerpendicular to each other
- DNone of these.
Explanation:
Force on a current carrying wire placed in a magnetic field is given by F = I (l × B) So when the wires are perpendicular the magnetic field produced by one of them will be along the length of the other and we know cross product of two vectors along the same direction is zero.
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
The sensitiveness of a moving coil galvanometer can be increased by decreasing
|
(a) The number of turns in the coil |
|
(b) The area of the coil |
|
(c) The magnetic field |
|
(d) The couple per unit twist of the suspension |
The distance between the body centred atom and a corner atom in sodium (a = 4.225 Å) is
|
(a) 3.66 Å |
(b) 3.17 Å |
(c) 2.99 Å |
(d) 2.54 Å |
A bar magnet of magnetic moment 3.0 A-m2 is placed in a uniform magnetic induction field of 2 × 10–5 T. If each pole of the magnet experiences a force of 6 × 10–4 N, the length of the magnet is
|
(a) 0.5 m |
(b) 0.3 m |
(c) 0.2 m |
(d) 0.1 m |
Assertion : A double convex lens (m = 1.5) has focal length 10 cm. When the lens is immersed in water (m = 4/3) its focal length becomes 40 cm.
Reason :
|
(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. |
|
(c) If assertion is true but reason is false. |
|
(d) If the assertion and reason both are false. |