When you heat an air-filled balloon, what happens inside with regard to the movement of air molecules?

a. the collisions of air molecules against the wall of the balloon are weaker.

b. the collisions of air molecules against the wall of the balloon are stronger.

c. the collisions of air molecules against the wall of the balloon do not change.

Waves that cause the most damage during an earthquake are a. surface waves c. s waves b. p waves d. ocean waves

What happens when you slowly pulled the carboard?

Asled is being held at rest on a slope that makes an angle θ with the horizontal. after the sled is released, it slidesa distance d1 down the slope and then covers the distance d2 alongthe horizontal terrain before stopping. find the coefficient ofkinetic friction μk between the sled and the ground, assumingthat it is constant throughout the trip. find the coefficient of kinetic frictionμk. express your answer in terms of someor all of the variables d1, d2, and θ.