Question

Samantha is driving forward at 27 meters per second (m/s) on 1 pointthe highway. Suddenly, she sees a moose on the road andslams on her brakes to save her brand new Kia. Her carcomes to a stop (0 meters per second) within 6 seconds.What is the acceleration (or deceleration in this case)?

A. 4.5 m/s²
B. 0 -4.5 m/s²
C. 50 m/s²
D. -16 m/s²

Answer 1

To calculate Samantha's car deceleration, we use the formula a = Δv/Δt with a change in velocity of -27 m/s over 6 seconds, which results in a deceleration of -4.5 m/s² (option B).

Step-by-step explanation:

To calculate the deceleration of Samantha's car, we can use the formula:

a = Δv/Δt

where a is the acceleration (or deceleration), Δv is the change in velocity, and Δt is the change in time.

Since Samantha is coming to a stop from 27 m/s, her change in velocity (Δv) is -27 m/s (final velocity of 0 m/s minus initial velocity of 27 m/s). The time taken (Δt) to come to a stop is 6 seconds.

Plugging these values into the formula:

a = (-27 m/s) / 6 s = -4.5 m/s²

This negative sign indicates that it is a deceleration. Therefore, the correct answer is B. -4.5 m/s².