Question

(i). State the kind of motion represented by OA and AB.
(ii). What does the slope of v-t graph represent?
(iii). Which part represents uniform retardation of the body? Also find the retardation.
(iv). Find the distance travelled by the body under constant velocity.

Answer 1

Answer:

(1) OA represents uniform acceleration since the slope of OA in the velocity-time graph is having a uniform positive slope. AB represents the uniform velocity of 20 ms-1. Since the slope of AB is zero hence, acceleration is zero.

(2) After 10s, the velocity is 20 ms-1 up to 30s and after 30 s, the velocity is uniformly restarted to zero after 40 s.

(3) Retardation is uniform and it is equal to the slope of BC, i.e. slope of BC = B D D C = 20 40 − 30 BDDC=2040−30 = 2ms-2

(4) Distance covered by the body between the 10th and 30th second = 20 x 20 = 400 metres