You are using a constant force (same amount of force each time) to accelerate a kid on a sled. Suddenly another kid jumps on, doubling the mass you are pulling. What happens to the acceleration?

Aray of light traveling parallel to the principal axis of a concave mirror will be reflected through the mirror's

Can you match these to the correct definition

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.