The impact of a truck colliding at 16 km/h with a concrete pillar caused the

bumper to indent only 7.4 cm. The truck stopped. Determine the acceleration of the

truck during the collision.

We calculate as follows:

Indent = 7.4 cm = 0.074 meters

Assuming uniform acceleration, the average speed during the impact = 16/2 = 8 km/hr

d = r*t

t = d/r = 0.074/8 = 0.00925 hr

a = 16 / 0.00925 = 1729.73 km/hr^2