posted by Dale .
A car that weighs 15,000 N is initially moving at 60km/hr when the brakes are applied. The car is brought to a stop in 30m. Assuming the force applied by the brakes is constant, determine the magnitude of the braking force.
Vf^2=Vi^2 + 2ad
but a= force/mass
so when you finally solve this, force will be negative: what does that mean?