×
Log in to StudySoup
Get Full Access to University Physics - 13 Edition - Chapter 9 - Problem 68p
Join StudySoup for FREE
Get Full Access to University Physics - 13 Edition - Chapter 9 - Problem 68p

Already have an account? Login here
×
Reset your password

Engineers are designing a system by which a falling mass m

University Physics | 13th Edition | ISBN: 9780321675460 | Authors: Hugh D. Young, Roger A. Freedman ISBN: 9780321675460 31

Solution for problem 68P Chapter 9

University Physics | 13th Edition

  • Textbook Solutions
  • 2901 Step-by-step solutions solved by professors and subject experts
  • Get 24/7 help from StudySoup virtual teaching assistants
University Physics | 13th Edition | ISBN: 9780321675460 | Authors: Hugh D. Young, Roger A. Freedman

University Physics | 13th Edition

4 5 1 263 Reviews
28
2
Problem 68P

Engineers are designing a system by which a falling mass m imparts kinetic energy to a rotating uniform drum to which it is attached by thin, very light wire wrapped around the rim of the drum (?Fig. P9.62?). There is no appreciable friction in the axle of the drum, and everything starts from rest. This system is being tested on earth, but it is to be used on Mars, where the acceleration due to gravity is 3.71 m/s2. In the earth tests, when m is set to 15.0 kg and allowed to fall through 5.00 m, it gives 250.0 J of kinetic energy to the drum. (a) If the sys-tem is operated on Mars, through what distance would the 15.0-kg mass have to fall to give the same amount of kinetic energy to the drum? (b) How fast would the 15.0-kg mass be moving on Mars just as the drum gained 250.0 J of kinetic energy?

Step-by-Step Solution:

Solution 68 P Step 1: Data given Mass on earth m = 15 kg Distance on earth de= 5.0 m Kinetic energy of the drum K = 250.0 J 2 Gravitational force on Mars gM = 3.71 m/s We need to find the distance of fall to get same amount of kinetic energy on Mars Considering the diagram given This is obtained using KE = PE K + K + mgh = 0 m drum f The kinetic energy of mass is given by Km= 1/2 mv 2 f The kinetic energy of drum is given by Kdrum = 1/2 I o2 Here = vo/R f o The ratio of K drum and K m is given by Kdrum 1/2 Io Km = 1/2 mv2 f Kdrum = I/mR 2 Km o Here we can see that the kinetic energy does not depend on final velocity v f Hence K Mars = K Earth = v Mars = v Earth Hence we have the distance as GE G × de= d m M Substituting the values we get 9.8 m/s 3.71 m/s× 5.0 m = 13.2 m Hence the distance from the Earth is 13.2 m

Step 2 of 2

Chapter 9, Problem 68P is Solved
Textbook: University Physics
Edition: 13
Author: Hugh D. Young, Roger A. Freedman
ISBN: 9780321675460

Other solutions

People also purchased

Related chapters

Unlock Textbook Solution

Enter your email below to unlock your verified solution to:

Engineers are designing a system by which a falling mass m