forces concept1
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TRANSCRIPT
Force and Motion
• Mac was a lonely soccer ball. Mac sat for hours and often pondered about the forces keeping him at rest on the green soft grass of his soccer field.
• Mac decided there were at least three forces acting upon him to keep him still.
• Can you name them?
• Correct! Air pressure, gravity, and the ground are all forces that keep him at rest.
• The forces are balanced since the net force results in zero movement.
• One day, a kid walks up to Mac and kicks him 15 yards eastward!
• The force of the kick is an unbalanced force and causes Mac to move.
• In flight, other unbalanced forces act upon Mac, that make him fall back to the ground and eventually comes to rest again.
• Name at least two of these unbalanced forces.
• Correct! Friction (Air Resistance) and gravity act upon Mac, slowing him down, until he comes to rest.
• Once at rest, the original three balanced forces (what are they?) act upon Mac again to keep him at rest.
• Now the same kid comes up and kicks Mac once again, sending him into the air. However, this time a nearby cliff causing him to fall at at increasing speed.
• When mac hits the ground, another unbalanced force(the ground) acts upon him, slowing him down.
• Additional forces now act on Mac slowing him down even more.
• What are two of these forces?
• Correct! Once again gravity and air resistance (friction) are unbalanced forces resulting in a change of speed.
• Eventually, these unbalanced forces cause Mac to slow down come to a rest.
• Once at rest, the original balanced forces(what are they?) act upon Mac to hold him still again.
• Until another unbalanced force causes him to move from his station in life.
• Morale:
• Sometimes boredom is better than an unbalanced force.