Two air-track carts move toward one another on an air track. Cart 1 has a mass of 0.34 kg and a speed of 1.1 m/s . Cart 2 has a mass of 0.68 kg and a speed of 0.55 m/s. Calculate the system's kinetic energy.

Answer 1

Before or after the collision?
Before the collision, you just add up the separate kinetic energies (mV^2/2) of each.