Question

The brakes are applied to a car traveling on a dry, level highway. A typical value for the magnitude of the car's acceleration is 4.60 m/s2. If the car's initial speed is 31.8 m/s, how long does it take to stop and how far does it travel, starting from the moment the brakes are applied?

Answer 1

a)t=6.91S

b)x=109.91m

Step-by-step explanation:

To solve the first part of this problem we use the following equation

t=(Vf-Vo)/a

Vf=final speed=0

Vo=initial speed=31.8m/s

t=time

a=aceleration=-4.60 m/s2

t=(0-31.8)/-4.6=6.91s

B )

For the second part of this problem we use the following equation

X=(Vf^2-Vo^2)/2a

X=(0^2-(-31.8)^2)/(2*-4.6)=109.92m