Dark matter is missing stars that have fallen from the sky.

true or false

How do the particles in an atom differ in electrical charge

Which statement about the physical change of liquid water boiling into steam is true? The heat added represents an energy change. The action cannot be reversed. The steam cannot conserve mass. The weight lost represents a mass change.

The launching velocity of a missile is 20.0 m/s, and it is shot at 53° above the horizontal. What is the horizontal component of the velocity at launch?

Which of the following is a contact force? A. Air resistance B. Magnetic force C. Gravity D. Electrical force

An object moving with uniform acceleration has a velocity of 14.0 cm/s in the positive x-direction when its x-coordinate is 2.85 cm. If its x-coordinate 3.15 s later is - 5.00 cm, what is its acceleration?

Which type of wave experiences a change in speed when entering a new medium? a) only sound waves b) both sound and light waves c) only light waves d) neither sound or light waves

Three basic classes of collisions include all but which of the following?

How does the use of biomass energy to create electricity harm the environment

Which physical property of iron made it popular for use in weapons? 1. Magnetism 2. Luster 3. Malleability 4. Ductility

a 2 kg rock is dropped from the top of a 30 m High building calculate the ball at the time that it strikes the ground