A railroad car with a mass of 30,000 kg is moving at 2.0 m/s when it runs into an at-rest freight car with an equal mass. the cara lock together. what is their final velocity?

A. 2.0 m/s

B. 0.5 m/s

C. 60,000 kg-m/s

D. 1.0 m/s

A little girl is going on the merry-go-round for the first time, and wants her 49 kg mother to stand next to her on the ride, 2.3 m from the merry-go-round's center. If her mother's speed is 4.

Which of the following colors has the highest photon energy? A. Blue B. Green C. Yellow D. Red Explain your reasoning.

Match each media portrayal with the type of behavior the media portrayal is likely to encourage. Safer behavior Hero driving fast and escaping danger Riskier behavior Hero attending a funeral of someone who died in a car accident

A 2.37-kg rock is released from rest at a height of 22.2 m. ignore air resistance and determine (a) the kinetic energy at 22.2 m, (b) the gravitational potential energy at 22.2 m, (c) the total mechanical energy at 22.

Batteries supply DC, direct current, which does not change in direction over time, though eventually they get exhausted.

A machine with a mechanical advantage of 10 is used to produce an output force of 250 newtons. What input force is applied to this machine

Why do you float in space

How does physical change affect the identity of a substance

A scientist pours grape juice on three identical white shirts He then uses three different cleaning products on the shirts and measures how clean they get what is the independent variable in this experiment

What part of the atom does nuclear radiation come from?