Question

10.At the park, you jump from the top of a picnic table down to the ground. Bending your knees as you land is easier on your knees because your stopping time is __________ when you land straight-legged.

a.longer than

b.same as

c.less than

11.The acceleration of gravity, as measured at the surface of Earth, is 9.8 m/s/s, but at the altitude of the space station, about 200 miles up, the acceleration is actually a bit larger.

True

False

14.

One can describe the y-coordinate equation for a free-fall trajectory,

with this phrase:

a.the law of universal gravitation.

b.the equation of reversal, colloquially known as "What goes up must come down."

c.time evolution equation for the y-coordinate

d.the free-fall version of the Pythagorean Theorem.

17.Galileo vs. Aristotle

• Galileo proposed a state of motion with constant velocity and no external forces acting.
• Aristotle viewed constant velocity as possible...

a.during the first second of free-fall.

b.whenever gravity acts but in no other situation.

c.but only if an external force makes the object move.

d.and, in fact, the only kind of motion.

Answer 1