Question

A car starting from rest acquires a velocity of 15m/s in 5 seconds. Calculate: (i) Its acceleration and (ii) the distance moved by it. ​​

Answer 1

Explanation:

Initial velocity (u) = 0m/s

Because the body stars from rest

Time (t) = 5 sec

Final velocity = 15m/s

Using 1st equation of motion:-

➝ v = u + at

➝ 15 = 0 + a(5)

➝ 5a = 15

➝ a = $\dfrac{15}{5}$

➝ a = 3

∴ Acceleration = 3m/s²

Using 3rd equation of motion:-

➝ s = ut + ½ at²

➝ s = (0 × 5) + ½ × 3 × (5)²

➝ s = ½ × 3 × 25

➝ s = $\dfrac{75}{2}$

➝ s = 37.5m

∴ Distance moved = 37.5m

Answer 2

Explanation:

For acceleration

a= u-v/t

=0-15/5

=3m/s^2