A65.2-kg skier coasts up a snow-covered hill that makes an angle of 33.3 ° with the horizontal. the initial speed of the skier is 8.05 m/s. after coasting a distance of 1.26 m up the slope, the speed of the skier is 4.54 m/s. (a) find the work done by the kinetic frictional force that acts on the skis. (b) what is the magnitude of the kinetic frictional force?

Astone weighing 1.5 kilograms is resting on a rock at a height of 20 meters above the ground. the stone rolls down 10 meters and comes to rest on a patch of moss. the gravitational potential energy of the stone on the moss is joules.

Aheat engine that operates on a carnot cycle has an efficiency of 0.420 when its low-temperature reservoir is at 10 ∘c. part aby how many degrees celsius must you increase the temperature of the high-temperature reservoir to increase the efficiency to 0.600 if you continue to use the same low-temperature reservoir?

The two metal spheres in the figure are connected by a metal wire with w switch in the middle. initially the switch is open. sphere 1, with the larger radius, i'd given a positive charge. sphere 2, with the smaller radius, is neutral. then the switch is closed. afterward, sphere 1 has charge q1, is at potential v1 and the electric field strength at its surface is e1. the values for sphere 2 are q2, v2, and e2. a. is v1 < ,> , or = to v2? explain. b. is q2 < , > , or = explain? c. is e1 < ,> ,or = to e2? explain?