Question

A car is traveling at 35.8 m/s. What acceleration would it have if it took 2.0 s to come to a complete stop?

Answer 1

Answer:

$\boxed {\boxed {\sf a= -17.9 \ m/s^2}}$

Explanation:

Acceleration is equal to the change in velocity over the change in time.

$a=\frac{v_f-v_i}{t}$

The initial velocity is 35.8 meters per second. The final velocity is 0 meters per second when the car comes to a complete stop. The time is 2.0 seconds.

$v_f= 0 \ m/s \\v_i= 35.8 \ m/s \\t= 2 \ s$

Substitute the values into the formula.

$a=\frac{0 \ m/s - 35.8 \ m/s }{2 \ s}$

Solve the numerator.

$a= \frac{ -35.8 \ m/s} {2 \ s}$

Divide.

$a= -17.9 \ m/s/s = -17.9 \ m/s^2$

The car's acceleration is -17.9 meters per square second. The acceleration is negative because the car was coming to a stop and slowing down.