1. 1) How much work is required to do the following? Is the energy entering or l
ID: 2114271 • Letter: 1
Question
1. 1) How much work is required to do the following? Is the energy entering or leaving the system?
a. Raise a 10 kg mass 0.5 m
b. Lower a 5 kg mass 0.1 m
c. Raise a 15 kg mass by 0.5 m, and then lower it back to its original starting position
2) How much mechanical energy expenditure is required to do the following?
a. Raise a 10 kg mass 0.5 m
b. Lower a 5 kg mass 0.1 m
c. Raise a 15 kg mass by 0.5 m, and then lower it back to its original starting position
Work shown to number 1 and 2 would be greatly appreciated! Need all parts of 1 and 2.. a,b, and c. Also 1 wants to know is the energy entering or leaving the system for a,b, and c.
Explanation / Answer
work = force * displacement
case -1
a) w = 10*9.8*0.5 = 49 J,energy is entering into system
b)w =-5*0.1*9.8= -4.9 J ,energy is leaving the system
c)w = 0 . since displacement is zero
case -2
mechanical energy = sum of potential and kinetic energy
a) change in mechanical energy = 10*9.8*0.5 = 49 J ( + sign means gain of mechanical energy)
b) change in mechanical energy = - 5*0.1*9.8 = - 4.9 J ( - sign means loss of mechanical energy)
c) change in mechanical energy = 0 ,,,nochange
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.