Write true or false for each statement:

(a) Two trains going in opposite directions with the same speed are at rest relative to each other.

(b) A ball is thrown vertically upwards. Its motion is uniform throughout.

(c) The motion of a train starting from one station and reaching at another station is non-uniform.

(d) A motion which repeats itself after a fixed interval of time is called periodic motion.

(e) A ball thrown by a boy from a roof-top has oscillatory motion.

(f) Mass has both magnitude and direction.

(g) Weight always acts vertically downwards.

(h) Mass varies from place to place but weight does not.