Question

For questions A, B, C, and D. Determine if the Kinetic Energy will increase, decrease or stay the same based on the directions of their force and velocity vectors.

Answer 1

Explanation:

KE = 1/2*m*v^2

mass won't change

but velocity is

A: the force is pushing against the direction of the object, so velocity is decreasing, so KE is decreasing

B: the F net line is pretty much straight up, which means there is no net force pushing to the left, but velocity is still increasing

Why? Because if you use the pythagorean theorem, the hypotenuse is always longer than the legs.

Note: velocity only ever stays the same if there is no net force (or 0 acceleration), so all four of these are either decreasing or increasing

C: there is a net force to the right, so velocity is increasing

D: There is a net force to the right but velocity is to the left, so velocity is decreasing

Hope I got these right