What two things must you know to find the

momentum of an object?

: (anyone?

Which of the following observations demonstrates the differences between speed of light and speed of sound? (Note, they are all true, but which one represents the difference in the speed?)) A.

The statement, "Energy can neither be created nor destroyed, but can change from one form to another," is what law?

Billy pulls his friend Sue on a sled at a constant velocity with a horizontal force of 200 N. The weight of the sled and Sue is 400 N. Which way will the sled move if Billy suddenly starts to pull with a force of 600 N?

The specific heat of substance X is 200 J/g*C, how much heat is required to change the temperature of 2.0 grams of substance X from 35 degrees Celsius to 55 degrees Celsius?

How many neutrons are present in an atom of iron-54? A) 26 B) 28 C) 30 D) 54

What is the density of an unknown metal that has a mass of 158 g and a volume of 20 ml

An electron is located on the x axis at x0 = - 9.31*10-6 m. Find the magnitude and direction of the electric field at x = 9.39 * 10-6 m on the x axis due to this electron.

Earth attracts a person with a gravitational force of 7.0 * 102 newtons. What is the magnitude of the force with which the individual attracts Earth? 3.0 * 10² newtons 7.0 * 10² newtons 8.5 * 10² newtons 9.8 * 10² newtons

The productive cycle of a human is usually regulated by

Winston stands on the edge of a building's flat roof, 12 m above the ground, and throws a 147.0-g baseball straight down. the ball hits the ground at a speed of 18 m/s. what was the initial speed of the ball?