Question

A 2600 kg car traveling to the north is slowed

down uniformly from an initial velocity of 23.7
m/s by a 6750 N braking force acting opposite
the car’s motion.
a) What is the car’s velocity after 1.73 s?
Answer in units of m/s.

Can anyone provide a formula? I used Ft=m(vf-vi) and continuously got -21.559 but thats not correct... please help, i will give you so many points, i am so desperate

Answer 1

19.2 m/s

Step-by-step explanation:

Let's say north is the positive direction.

Impulse = change in momentum

F Δt = m Δv

(-6750 N) (1.73 s) = (2600 kg) (v − 23.7 m/s)

-11677.5 Ns = (2600 kg) (v − 23.7 m/s)

-4.49 m/s = v − 23.7 m/s

v = 19.2 m/s