A body moving with a constant velocity on normal ground initially has an energy of 1000 J. If the final energy is 800 J, what is the work done and which force causes this work?
A. 200 J, gravity
B. -200 J, friction
C. 200 J, friction
D. -200 J, gravity
Answer:B
A body moving with a constant velocity on normal ground initially has an energy of 1000 J. If the final energy is 800 J, what is the work done and which force causes this work?
A. 200 J, gravity B. -200 J, friction C. 200 J, friction D. -200 J, gravity