BR physics chapter 3 passage 2 number 9

[2010premed]

---

Members do not see this ad.

The child must traverse a certain distance over the rough surface to come to a complete stop. If the slide designers wished to stop the child in half that distance, the work required by friction would necessarily:
A. double
B. quadruple
C. remain the same
D. halve

Answer: C

 

[Rayhaan]

Work, not force. Work remains the same, only the force or the distance change. Why? Because work is in Joules (energy). Energy difference is the same from w/e his starting energy is, to his final energy, and work is just the difference. So work remains the same.

 

[2010premed]

yes this makes sense now... thanks