Question

A bus accelerates uniformly from 54 KM per hour to 72 KM per hour in 10 seconds.calculate
A)acceleration in m/second square
B)distance covered by the bus in meters during the interval

Answer 1

Explanation:

Given :-

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 seconds  

To Find :-

(a) Acceleration

(b) Distance traveled

Formula to be used :-

a = (v - u)/t  and v² = u² + 2aS  

Solution :-

(a) Acceleration

Acceleration, a = (v - u)/t  

⇒ a = (20-15)/10

= 0.5 m/s²

(b) Distance traveled by the bus  

v² = u² + 2aS  

⇒ 20² = 15² + 2 × 0.5 × S  

⇒ 400 = 225 + 1×S

⇒ 400 - 225 = S

⇒ S = 175 m

Hence, the acceleration and distance traveled​ by bus is 0.5 m/s² and 175 m.