Cindy exerts a force of 40 newtons and moves a chair 6 meters. her brother andy pushes a different chair for 6 meters while exerting a force of 30 newtons.

andy does (less or more? ) work than cindy. the difference of their amounts of work is (how many? ) nm.

Afisherman notices that his boat is moving up and down periodically without any horizontal motion, owing to waves on the surface of the water. it takes a time of 2.20 s for the boat to travel from its highest point to its lowest, a total distance of 0.670 m . the fisherman sees that the wave crests are spaced a horizontal distance of 5.80 m apart. (a) how much is the wavelength? (b) find the period of the wave. (c) how fast are the waves traveling? (d) what is the amplitude a of each wave?

A20 cm long spring is attached to a wall. the spring stretches to a length of 22 cm when you pull on it with a force of 100 n. what is the spring constant

What component of earth’s atmosphere exists entirely as a result of photosynthesis?