2. A 10 kg block slides from rest from the top of a 100 m long ramp that is elevated at one end by 50 m. It reaches a speed of 20 m/s at the bottom. a. Find the work done by friction on the block and the force of friction. b. What power is needed to pull the block up the plane at a constant speed of 5 m/s? c. A 2 kg hoop with radius 50 cm rolls without slipping from the top of the incline. Use conservation of energy to find its speed at the bottom and its rotational kinetic energy.

2. A 10 kg block slides from rest from the top of a 100 m long ramp that is elevated at one end by 50 m. It reaches a speed of 20 m/s at the bottom. a. Find the work done by friction on the block and the force of friction. b. What power is needed to pull the block up the plane at a constant speed of 5 m/s? c. A 2 kg hoop with radius 50 cm rolls without slipping from the top of the incline. Use conservation of energy to find its speed at the bottom and its rotational kinetic energy.

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter11: Energy And Its Conservation

Section: Chapter Questions

Problem 65A

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