Suppose a planet has half the mass of Earth but the same radius. An astronaut stands on the surface
of the planet and drops a rock from a height of
2.4 m. How much longer does it take the rock to
hit the ground on that planet than it would on
Earth?
(a) 1.2 times longer
(b) "2 times longer
(c) 2 times longer
(d) 4.8 times longer
explain please!

After a big snowfall, you take your favorite rocket-powered sled out to a wide field. the field is 195 m across, and you know that your sled accelerates at a rate of 3.65 m/s2 when the rocket is on. how much time will it take the sled to cross the field starting from rest, assuming the rocket is on the whole time?

While goofing off at the ice skating rink, a student takes off her shoes and places each of them on the ice. her friend, a hockey player, then shoots a hockey puck at each shoe. the first puck immediately comes to rest after it collides with the left shoe. the second puck rebounds after it collides with the right shoe. if each hockey puck has the same incoming speed, which shoe has greater speed after the collision? the right shoe. both shoes have the same speed. the left shoe.

What are the factors that affect the resistance of a wire?