A missile is fired form the back of a stationary truck. The missile takes off at a speed of 47.9 m/s and has a mass of 31.8 kg. If the truck has a mass of 1.15×103 kg, what is the recoil speed of the truck?
conserve momentum
31.8*47.9 + 1150v = 0
31.8*47.9 + 1150v = 0