A 59 g particle is moving to the left at 21 m/s . How much net work must be done on the particle to cause it to move to the right at 49 m/s

Atrain departs from its station at a constant acceleration of 5 m/s. what is the speed of the train at the end of 20s?

Ametal ball with a mass of 0.028 kg is dropped from rest at a height of 1.0 meters above the ground. assuming the energy in the ball is conserved, how much kinetic energy will the ball have when it is 0.5 meters above the ground?

The current in a hair dryer measures 11 amps. the resistance of the hair dryer is 12 ohms. what is the voltage?unit: