Class Management Help Homework - Chapter 7 Begin Date: 8/29/2017 12:00:00 AM --
ID: 1789455 • Letter: C
Question
Class Management Help Homework - Chapter 7 Begin Date: 8/29/2017 12:00:00 AM -- Due Date: 10/25/2017 11:59:00 PM End Date: 12/21/2017 12:00:00 AM (4%) Problem 11: A box m = 5.5 kg rests on a horizontal frictionless counter compressing a spring k = 125 N/m by a distance ofd=0.29 m > What is the average power supplied by the spring, in watts, if the spring is released? Grade Summary 0% 100% Potential sin() | cos() | tan() | | ( | ) | 7 | 8 | 9 cotan0 asinO acos0 atan) acotansinh) cosh)tanh cotanh0 Attempts remaining: 10 % per attempt) detailed view 1 2 3 0 END oDegrees Radians CLEAR Submit Hint I give up! Hints: 1 % deduction per hint. Hints remaining: 3 Feedback: 0% deduction per feedback.Explanation / Answer
t = T/4 = (2pi/4) sqrt(m/k) = (2 x 3.14/4) sqrt(5.5/125) = 0.33 sec
W = work done = (0.5) k d2 = (0.5) (125) (0.29)2 = 5.3 J
average power is given as
P = W/t = 5.3/0.33 = 16.1 Watt