Answer:
33.2 m/s
Explanation:
In order to solve this problem, we need to know the mass of the car.
Here, we assume that the mass of the car is
m = 1 kg
Then, we can apply the work-energy theorem, which states that the work done on the car by the braking force is equal to the change in its kinetic energy:
[tex]W=\Delta E_k\\Fd=\frac{1}{2}mv^2-\frac{1}{2}mu^2[/tex]
where:
F = -3.87 N is the force applied by the brakes (negative because its direction is opposite to the motion of the car)
d = 4.92 m is the displacement of the car
u = 33.8 m/s is the initial velocity of the car
v is the final velocity of the car
Therefore, solving for v, we find:
[tex]v=\sqrt{\frac{2Fd}{m}+u^2}=\sqrt{\frac{2(-3.87)(4.92)}{1}+(33.8)^2}=33.2 m/s[/tex]
