A student is running an experiment to determine the relationship between force and acceleration. Given a cart, a track, and 3 mass bars of equal mass, the student uses a spring that can apply varying amounts of force to the cart and a
motion sensor and graphing software to collect acceleration data.
How should the student run this experiment? Circle the letter of your choice.

A.
Run trials with zero added mass, then run trials with increasing mass, until all 3 mass bars are added, increasing
the force as mass is added.

B.
Run trials with zero added mass, then run trials with increasing mass, until all 3 mass bars are added, holding
force constant as mass is added.

C.
Run trials with zero added mass, then run trials with all mass bars added, increasing the force as mass is added.

D.
Run trials with any constant mass, increasing force as more trials are collected.

Acup of coffee sits on the dashboard of an automobile. the car goes around a sharp curve. even though you hold the cup still, coffee still splashes out. this can best be explained due to a) density. b) friction. c) gravity. d) inertia.

Amoving electron has kinetic energy k1. after a net amount of work w has been done on it, the electron is moving one-quarter as fast in the opposite direction. (a) find w in terms of k1. (b) does your answer depend on the final direction of the electron's motion?

Astudent throws a water balloon with speed v0 from a height h = 1.76 m at an angle θ = 21° above the horizontal toward a target on the ground. the target is located a horizontal distance d = 9.5 m from the student’s feet. assume that the balloon moves without air resistance. use a cartesian coordinate system with the origin at the balloon's initial position. (a) what is the position vector, rtarge t, that originates from the balloon's original position and terminates at the target? put this in terms of h and d, and represent it as a vector using i and j. (b) in terms of the variables in the problem, determine the time, t, after the launch it takes the balloon to reach the target. your answer should not include h. (c) create an expression for the balloon's vertical position as a function of time, y(t), in terms of t, vo, g, and θ. (d) determine the magnitude of the balloon's initial velocity, v0, in meters per second, by eliminating t from the previous two expressions.