Exploration 6.3: The Gravitational Force and Work

Please wait for the animation to completely load.

A 1-kg ball is subjected to the force of gravity as shown in the animation (position is given in meters and time is given in seconds).  The ball starts at x = 0 m and y = 0 m.  You can vary the ball's initial velocity and view how this affects the motion of the ball and the ball's kinetic energy.  Also shown are the graphs of force cos(θ_y) vs. position_y and kinetic energy vs. position_y where θ_y is the angle between the gravitational force and the ball's infinitesimal y displacement.   Restart.

With v_0x = 0 m/s and v_0y = 0 m/s,

1. In what direction does the net force on the ball point?
2. How would you describe the kinetic energy vs. position graph?

With v_0x = 10 m/s and v_0y = 0 m/s,

3. What is the ball's minimum kinetic energy?

With v_0x = 10 m/s and v_0y = 10 m/s,

4. How would you describe the KE vs. position graph?  Be explicit about what happens to the kinetic energy.
5. What is the condition for the work done by gravity to be zero?
6. What is the ball's minimum kinetic energy? 

With v_0x = -10 m/s and v_0y = 10 m/s,

7. How would you describe the kinetic energy vs. position graph?  Be explicit about what happens to the kinetic energy.
8. What is the condition for the work done by gravity to be zero?
9. What is the ball's minimum kinetic energy?

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