Question

A car is moving at 10 m/s and speeds up uniformly to a speed of 30 m/s in a time of 5 seconds. What is the car's acceleration? Be sure to include the proper label.

A. 4 m/s²
B. 6 m/s
C. 4 m/s
D. 6 m/s²

Answer 1

To calculate the car's acceleration, you take the change in velocity (20 m/s) and divide it by the time (5 s), resulting in an acceleration of 4 m/s², which is option A.

Step-by-step explanation:

The car's acceleration can be calculated using the formula for uniform acceleration, which is

a = Δv / Δt, where Δv is the change in velocity and Δt is the time taken for that change. In this case, the car's initial velocity (v0) is 10 m/s and the final velocity (v) is 30 m/s. The time taken, t, for this increase is 5 seconds. Thus, the change in velocity (Δv) is

v - v0 = 30 m/s - 10 m/s = 20 m/s.

To find the acceleration (a), we divide the change in velocity by the time taken:

a = Δv / Δt = 20 m/s / 5 s = 4 m/s².

Therefore, the car's acceleration is 4 m/s², which corresponds to option A.