1. The problem statement, all variables and given/known data Two cars are in opposite to each other. First car is 1000kg, second car is 2000kg. First car moves towards the second one with a velocity of ( neglect friction between the car's wheels and the asphalt ): a) 30 km/h b) 40 km/h c) 50 km/h Second car stands still untill the collision appears ( velocity = 0km/h ). Calculate the length of route traveled by the second car after the collision ( assume the friction coefficient between the car's wheelsand the asphalt as T = 0.5 ). If needed simplify the calculations by assuming both cars can only move forward/backward and can not turn ( two points of mass in an inertial frame ). 2. Relevant equations I think that pretty much only thing I need here is Newton's: F = ma [ N = kg * m/s^2 ] v = at -> a = v/t [ m/s * 1/s ] Although there is other problem, described below. 3. The attempt at a solution So I managed to calculate the force acting on the second car after an impact, simply by substituting them into: F = ma [N] = m * v/t [ kg * m/s * 1/s ] F30 = 1000 * 5.55 * 1/t^2 F40 = 1000 * 8.33 * 1/t^2 F50 = 1000 * 11.11 * 1/t^2 But how do I get the time for the equation? This bugs me, is there another equation for acceleration I can use there? Also, when I calculate the forces, how do I actually calculate the path traveled by the car, when I have to include friction ( I belive without it, car would just go on and on, without stopping ).