Answer:
Second one
Explanation:
Lying on the floor is something you can do with the least amount of energy
Answer: softer
The sound waves become weaker, so to an observer this wave is lighter sound.
Power = Work done/Time taken
So, keeping this in mind,we can solve it as follows:
= 700/3.1
= 7000/31
= 225.80 W
Yes. Think of block sitting on top of a bigger block. If the bottom block moves, it will drag the top block with it. Since the force of friction on the small block and its displacement are in the same direction, the "work" is positive. The static friction is a passive force, It is not a source of energy; it transmits the force placed on the bottom block. (And the "work" done by the friction on the bottom block is exactly the negative of the work done on the top block.)
