A boy on a swing is pulled to a position 2.34 m off the ground and released. At the fastest and lowest point m S of the swing the boy is 0.50 m off the ground and travelling 3. The percent efficiency of this swing system is: A) 70% B) 25% C) 50% D) 10% A ball is dropped from a height of 3.0 m. As it falls A) its gravitational potential energy increases and its kinetic energy increases. B) its gravitational potential energy decreases and its kinetic energy increases. C) its gravitational potential energy decreases and its kinetic energy decreases. D) its gravitational potential energy increases and its kinetic energy decreases.

A boy on a swing is pulled to a position 2.34 m off the ground and released. At the fastest and lowest point m S of the swing the boy is 0.50 m off the ground and travelling 3. The percent efficiency of this swing system is: A) 70% B) 25% C) 50% D) 10% A ball is dropped from a height of 3.0 m. As it falls A) its gravitational potential energy increases and its kinetic energy increases. B) its gravitational potential energy decreases and its kinetic energy increases. C) its gravitational potential energy decreases and its kinetic energy decreases. D) its gravitational potential energy increases and its kinetic energy decreases.

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter8: Potential Energy And Conservation Of Energy

Section: Chapter Questions

Problem 65P: A block of mass 200 g is attached at the end of a massless spring of spring constant 50 N/m. The...

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