Which of the following is a simple machine?

If the Sun were scaled down to the size of a grapefruit, about how far would you have to walk from our classroom to reach Alpha Centauri, the closest star?

Control rods are used to prevent uncontrolled chain reactions from happening inside nuclear power plants.

Which of the following describes how a microwave heats food

A boy jumps from a wall 3m high. What is an estimate of the change in momentum of the boy when he lands without rebounding? A 5x10∧0 kgms-1 B. 5x10∧1 kgms-1 C. 5x10∧2 kgms-1 D. 5x10∧3 kgms-1

a 4.00 mC is 1.5m from a - 3.00mC charge. find the magnitude of the electrostatic force between these two charges. is the force attractive or repulsive?

Using the atomic symbol above report how many protons, neutron, and electrons an atom of neon contains.

Which of the following is not shorthand to describe one of the three types of ecological relationships? +/+ -/+ +/0 -/0

Which is a characteristic of an electromagnetic wave?

What does the ozone layer absorb? a. Microwaves c. UV radiation b. X-rays d. Infra-red radiation

An object is undergoing shm with period 0.900 s and amplitude 0.320 m. at t = 0 the object is at x = 0.320 m and is instantaneously at rest. calculate the time it takes the object to go (a) from x = 0.320 m to x = 0.160 m and (b) from x = 0.