Q1. A roller coaster (305 kg) moves from A (5.00 m above the ground) to B (23.0 m above the ground) Two non conservative forces are present: friction does -2.00 104 J of work on the car, and the chain mechanism does +3.00 104 J of work to help the car up a long climb. What is the change in the car's kinetic energy, ΔKE = KEf - KE0, from A to B?
Q2. A 64-kg man standing on a scale in an elevator notes that as the elevator rises, the scale reads 834 N. What is the acceleration of elevator?