When a fountain pen is taken in a high flying aeroplane, it leaks. A ballpoint pen does not have this problem. Explain how the ball point pen is able to overcome this problem.

A980-kg sports car collides into the rear end of a 2300-kg suv stopped at a red light. the bumpers lock, the brakes are locked, and the two cars skid forward 2.6m before stopping.the police officer, estimating the coefficient of kinetic friction between tires and road to be 0.80, calculates the speed of the sports car at impact. what was that speed?