Question

Consider two planetary orbits with the same energy E.  If the two planets have the same mass, but orbit A has a smaller angular momentum than orbit B, which of the following is true?

	A.	Orbit B is open.  Orbit A is closed.
	B.	Orbit B has a smaller semimajor axis than orbit A.
	C.	The period of orbit A is greater than that of orbit B.
	D.	Orbit A is more elongated (more eccentric) than B.

True or false: Light always moves on a straight path through space.

	A.	False.  The path of light is bent by gravity.
	B.	True.  Due to the speed of light being a universal constant, the path cannot be bent.

In the video I showed in the lecture, why does a plane flying in a parabolic trajectory simulate zero gravity?

	A.	Because the they fly so high that gravity is negligible.
	B.	Because parabolic motion causes normal forces that cancel the force of gravity.
	C.	Because all curved paths in a vertical plane feel weightless.
	D.	Because projectile freefall motion follows a parabolic arc and freefall motion feels weightless.

Answer 1