A 930 kg sports car collides into the rear end of a 2500 kg SUV stopped at a red light. The bumpers lock, the brakes are locked, and the two cars skid forward 2.6 m/s before stopping. The police officer, knowing that the coefficient of kinetic friction between tires and road is 0.80, calculates the speed of the sports car at impact.

Question

what was the speed?

Answer 1

consider momentum change
momentum before= impulse to stop.
930*v=force*time= force*distance/avgvelocity

930V= mu*totalmass*g*distance*2/V

V=sqrt (2*mu*totalmass*g*distance/930)

I cant see anything wrong with this analysis.

Answer 2

I'm not sure why I keep getting the wrong answer, but I do.

Thanks for the help anyway :D

Answer 3

type the following into g00gl and the first result which will yah00answers will help you:The police officer, knowing that the coefficient of kinetic friction between tires and road is 0.80, calculates the speed of the sports car at impact.

Answer 4

blah blah blah