Part I: Free-Body Diagrams
Please wait for the animation to completely load.
An 8-kg block is pushed across the floor (position is given in
centimeters and time is given in seconds). Push "play" and let the
animation run. Restart.
- Describe the motion.
- Sketch a possible free-body diagram for the block.
- What is the velocity of the block at t = 2-seconds? Show your work.
- What is the velocity of the block at t = 4-seconds? Show your work.
- What is the acceleration of the block? Show your work.
- Therefore, the net force in x-direction equals?
- Net force in the y-direction?
- Consider the forces in the x-direction (horizontal forces). Click
each of the four possible diagrams. The length of the vector represents
the magnitude of the force. Only one is a possible free-body diagram.
For each animation, indicate why it is or is not a possible force diagram.
- Based on this, sketch a complete free-body diagram.
- Explain any differences with your original sketch.
- Click on the
complete free-body diagram animation below.
- Does is agree with your sketch above? If not, explain why the animation
(and not your drawing) shows the correct free-body diagram.
Note that in this case, there is a frictional force, but the form of the
frictional force will be addressed later in this course.
Original problem and script:
Illustration 4.2, Physlet Physics
© 2004 by Prentice-Hall, Inc. A Pearson