The dog walked 5 meters backwards in the first 10 seconds, then 5 meters forward from 10-20 seconds. After 20 sec he was back where he started. Displacement (20sec) = zero.
Answer:
c) is negative
Explanation:
As we know that work done by a force is the product of force and displacement vector.
W= F.d
F= Force
d= displacement
The work done by friction force always negative because it try to oppose the motion and act opposite to the direction of displacement.So the work done by air resistance is negative.
c) is negative
I think the correct answer from the choices listed above is option D. Solar cells convert electromagnetic energy into electrical energy. This is because the photons from the rays of light are electromagnetic waves or particles. Hope this answers the question.
