Question

a car moving with a velocity of 54 km hr is accelerated so that its velocity becomes 72km/hr in 15sec. calculate the acceleration of the car

Answer 1

HI there !!

Initial velocity = u = 54km/hr = 54 × 5/18 = 15m/s

Final velocity = v = 72 km/hr = 72 × 5/18 =20 m/s 

Time = t = 15 sec

Law of motion :

v = u + at

20 = 15+ a × 15

20 = 15 + 15 a

15a + 15 = 20

15a = 20 - 15

15 a = 5

a = 5/15

a = 0.33 m/s²

Answer 2

Initial velocity of the car u = 54 Kmh = 15 m/s

Final velocity v = 72Kmh = 20 m/s.

From the equation, v = u + at

a = v - u /t

= 20 - 15/15

= 5 / 15

= 0.33 m/s².

:)