(2) A rock with mass 0.15 kg is placed in a sling shot and the elastic band of the sling shot is stretched by 70.0 cm from its relaxed position to store elastic potential energy in it. The spring constant of the elastic band is 28.5 N/m. The elastic band is then released to launch the rock. What is the speed of the rock when it leaves the sling shot if (a) no heat is produced when the elastic band is released? (answer: 9.7 m/s) (b) 2.8 J of heat energy are produced when the elastic band is released? (answer: 7.5 m/s)

(2) A rock with mass 0.15 kg is placed in a sling shot and the elastic band of the sling shot is stretched by 70.0 cm from its relaxed position to store elastic potential energy in it. The spring constant of the elastic band is 28.5 N/m. The elastic band is then released to launch the rock. What is the speed of the rock when it leaves the sling shot if (a) no heat is produced when the elastic band is released? (answer: 9.7 m/s) (b) 2.8 J of heat energy are produced when the elastic band is released? (answer: 7.5 m/s)

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 79AP: Consider a block of mass 0.200 kg attached to a spring of spring constant 100 N/m. The block is...

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