Q. 61. In circular motion
(A) the direction of motion is fixed
(B) the direction of motion changes continuously
(C) the acceleration is zero
(D) the velocity is constant
Answer:
Explanation:
Q. 62. The unit of power is
(A) watt
(B) joule
(C) newton
(D) kelvin
Answer:
Explanation:
Q. 63. Which of the following involves electromagnetic induction?
(A) charge is put on a rod
(B) an electric current produces a magnetic field
(C) a magnetic field exerts a force on a current carrying wire
(D) relative motion between a magnet and a coil produces an electric current
Answer:
Explanation:
Q. 64. The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should be the position of the object?
(A) Between the principal focus and centre of curvature
(B) At the centre of the curvature
(C) Beyond the centre of the curvature
(D) Between the pole of the mirror and its principal focus
Answer:
Explanation:
Q. 65. The change in focal length of an eye lens is caused by the action of
(A) Retina
(B) Pupil
(C) Ciliary muscles
(D) Iris
Answer:
Explanation: