Question

A bus accelerates uniformly from 54km/h to 72 km/h in 10 seconds calculate . find (1) accelerates in m/second square .(2) distance cover by bus during thiss intervals.​

Answer 1

(i) Initial velocity, u = 72 km/h = 72×(5/18) m/s = 20 m/s

Final velocity, v = 54 km/h = 54×(5/18) m/s = 15 m/s

Time in which velocity changes is, t = 10 s

Acceleration, a = (v - u)/t

=> a = (15 - 20)/10 = -0.5 m/s^2

(ii) distance travelled by the bus

Its avg speed over the 10 sec is (15 + 20)/2 = 17.5 m/sec

17.5*10 = 175 meters