Sand is made of tiny pieces of rock that have been worn down by wind and water. explain why the formation of sand is a physical change.

1. a net force of 100 newton’s is applied to a wagon for 5 seconds. this causes the wagon to undergo a change in momentum of

Asolid cylinder and a cylindrical shell have the same mass, same radius, and turn on frictionless, horizontal axles. the cylindrical shell has light-weight spokes connecting the shell to the axle. a rope is wrapped around each cylinder and tied to blocks of equal masses that are held the same height above the ground. both blocks are released simultaneously. the ropes do not slip. which block hits the ground first? or is it a tie?

Which of the following types of electromagnetic radiation has the longest wavelength? a. infrared light b. visible light c. ultraviolet light d. microwaves