A motorbike moving with initial velocity 28 m s-1 and constant acceleration. Class 9

A motorbike moving with initial velocity 28 m s^-1 and constant acceleration. Class 9

Question 1.

A motorbike moving with initial velocity 28 m s^-1 and constant acceleration stops after travelling 98 m. Find the acceleration of the motorbike and the time taken to come to a stop. Class 9

Answer:

Given:

1. Initial velocity, u = 28 m s^-1
2. Final velocity, v = 0 m s^-1 (stops)
3. Distance, s = 98 m Finding acceleration:

Using v² = u² + 2as:

0² = 28² + 2 × a × 98

0 = 784 + 196a

196a = -784

a = -784 /196 = -4 m s^-2

The negative sign indicates the acceleration is opposite to the direction of motion (it is deceleration/retardation). The magnitude of acceleration = 4 m s^-2.

Finding time taken:

Using v = u + at:

0 = 28 + (-4) × t

4t = 28

t = 28 / 4 = 7 s