Question

1.) an object moves along the x axis, subject to the potential energy shown. The object has a mass of 1.1kg and starts at rest at point A. (a) what is the object’s speed at point B? (b) at point C? (c) at point D? (d) what are the turning points for this object?
2.) a 1250-kg car drives up a hill that is 16.2m high. During the drive, two nonconservative forces do work on the car: (i) the force of friction, and (ii) the force generated by the car’s engine. The work done by friction is -3.11x10^5J; the work done by the engine is +6.44x10^5J. find the change in the car’s kinetic energy from the bottom of the hill to the top of the hill.
3.) starting at rest at the edge of a swimming pool, a 72.0-kg athlete swims along the surface of the water and reaches a speed of 1.20m/s by doing the work Wncl=+161J. find the nonconservative work, wnc2, done by the water on the athlete.
4.) starting at rest at the edge of a swimming pool, a 72.0-kg athlete swims along the surface of the water and reaches a speed of 1.20m/s by doing the work Wncl=+161J. find the nonconservative work, wnc2, done by the water on the athlete.

Answer 1

If I'm not wrong #1 should be C