Question

A car with an initial velocity of 12 m/s comes to rest

in 3.5 s. What is the car's average acceleration during
braking? Give both magnitude and sign. i'm

Answer 1

- 3.4286 m/s²

Step-by-step explanation:

Acceleration a = (v - u)/t where v is the final velocity attained and u is the initial velocity and t the time taken to reach velocity v from u

Initial Velocity = 12 m/s
Final Velocity = 0 m/s

Difference in velocity = 0 - 12 = -12 m/s

t = 3.5 s

a = -12 m/s ÷ 3.5 s = - 3.4286 m/s²

The negative sign indicates that it is deceleration which is the opposite of acceleration and is because the velocity of the car is reducing