Question

A car traveling initially at the speed of 30 m/s slows down at the rate of -2m/s^2 for a distance of 60 meters. What is the car’s velocity after covering this distance?

Answer 1

Vf = 25.7 [m/s]

Step-by-step explanation:

To solve this problem we must use the following kinematics equation:

`v_(f) ^(2)= v_(i) ^(2)-(2*a*x)`

where:

Vf = final velocity [m/s]

Vi = initial velocity = 30 [m/s]

a = desacceleration = 2 [m/s^2]

x = distance = 60 [m]

Note: the negative sign in the equation means that the car slows down.

Now replacing:

`v_(f)^(2)=(30)^(2)-(2*2*60)\\ v_(f)^(2) = 660\\v_(f) =√(660) \\v_(f)=25.7[m/s]`