Which of the following statement is true?
a) whenever an object moves, work is being done
b) a large goes always means more work has been done
c) whenever a force is pit on an object, work is being done
d) in order for work to be done, a force must move an object over a distant

When a pair of 10-n forces act on a box of candy, the net force on the box is a 20 n. b about 14 n. c zero. d any of the above depending on the directions of forces.

Aheavy boy and a lightweight girl are balanced on a massless seesaw. the boy moves backward, increasing his distance from the pivot point. what happens to the seesaw? it is impossible to predict without knowing additional information. the side the boy is sitting on will tilt downward. the side the girl is sitting on will tilt downward. nothing; the seesaw will remain balanced.

Explain how the absorption of sound waves differs from the transmission of sound waves.