Guiding Questions: At the top, before that cart starts moving, how much Kinetic Energy does it have?
At the bottom, when the height is zero, how much Potential Energy does it have?
Does the total Energy in this system ever change, or is your total energy always constant?

Aboxcar traveling at 12 m/s approaches a string of 5 identical boxcars sitting stationary on the track. the moving boxcar collides and links with the stationary cars and they all move off together along the track. what is the final speed of the cars immediately after the collision? (you may take the mass of each boxcar to be 18,537 kg.)

True or false: the cycle of seasons on the earth is caused by the tilt of the earth on its axis toward and away from the sun.

Which of the following is the phase that results when the moon is on the opposite side of the earth from the sun? a. quarter moon b. crescent moon c. new moon d. full moon