15 beats are heard in 5 seconds when a piano key and a tuning fork of slightly higher frequency (440 hz) are struck at the same time. what is the frequency of the sound emitted by the piano key?

Which expression allows you to determine the mechanical advantage of an inclined plane? a. height of plane / input force b. length of plane / input force c. length of plane / height of plane d. height of plane / length of plane

If a tank filled with water contains a block and the height of the water above point a within the block is 0.8 meter, what is the pressure at point a?

What is the coefficient of kinetic friction μk between the block and the tabletop?