A 2 kg mass moving to the right makes an elastic head-on collision with a 4 kg mass moving to the left at 4 m/s. The 2 kg mass reverses direction after the collision and moves at 3 m/s. The 4 kg mass moves to the left at 1 m/s. What was the initial velocity of the 4 kg mass?

How would a small bar magnet be oriented when placed at position x?

A6.0-μf air-filled capacitor is connected across a 100-v voltage source. after the source fully charges the capacitor, the capacitor is immersed in transformer oil (of dielectric constant 4.5). how much additional charge flows from the voltage source, which remained connected during the process?

Identify the type of heat transfer occurring when chocolate melts in your hand