Which of the following is a physical change? a.) sawing a piece of wood. b.) burning a piece of wood. c.) rust forming on an iron fence. d.) a copper roof changing color from green to red.

When a book falls from a shelf to the ground without anyone pushing on it, no work is done on the book. true or false

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?

Match these items. 1. coulombs __force 2. ohms __emf 3. centimeters __resistance 4. newtons __charge 5. volts __length