Final answer:
The deceleration of the car is calculated using the formula a = ∆v/∆t, yielding a deceleration of -6 m/s², which corresponds to B) 6 m/s² as the correct answer.
Step-by-step explanation:
The truck of a passenger car applies brakes at a velocity of 30 m/s and comes to rest 5 seconds later. To determine the deceleration, we use the formula for acceleration (which in the case of slowing down is referred to as deceleration), which is a = ∆v/∆t. Here, ∆v (change in velocity) is 30 m/s (final velocity) - 0 m/s (initial velocity), and ∆t (time) is 5 seconds.
Now, we calculate the deceleration: a = (0 m/s - 30 m/s) / 5 s = -30 m/s / 5 s = -6 m/s². The negative sign indicates that it is a deceleration.
The correct answer to the question is B) 6 m/s².