ForcesWhat are they

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ForcesWhat are they?
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ForcesWhat are they?
Forces cause motion (a change in motion) or
tend to cause things to move.
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ForcesWhat are they?
Forces cause motion (a change in motion) or
tend to cause things to move.
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ForcesWhat are they?
Forces cause motion (a change in motion) or
tend to cause things to move.
Identifying forcesand what they act oncan be
confusing.
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An object moves because a force acts on it.
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An object moves because a force acts on it.
More a force (if not somehow canceled out)
causes an object to accelerate.
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An object moves because a force acts on it.
More a force (if not somehow canceled out)
causes an object to accelerate. Recall freefall
agrav 9.8 m/s2 (down)
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An object moves because a force acts on it.
More a force (if not somehow canceled out)
causes an object to accelerate. Recall freefall
agrav 9.8 m/s2 (down)
The object accelerates downward because the
Earths gravitational force acts on it. If the
ball were on a table that supported it then the
gravitational force would be canceled outand
acceleration would be 0.
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General Information about forces
A force is a push or a pull.
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General Information about forces
A force is a push or a pull.
A force acts on an object.
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General Information about forces
A force is a push or a pull.
A force acts on an object.
A force requires an agent.
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A force is a vector.
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A force is a vector.
A force can either be a contact force
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A force is a vector.
A force can either be a contact force or a
long-range force
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An object moves because a force acts on it.
More a force (if not somehow canceled out)
causes an object to accelerate. Recall freefall
agrav 9.8 m/s2 (down)
Fgrav (on ball)
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An object moves because a force acts on it.
More a force (if not somehow canceled out)
causes an object to accelerate. Recall freefall
agrav 9.8 m/s2 (down)
Fgrav (on ball)
Push or pull?...on what object?...agent?...contact
or long-range?
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If no force is acting on an object then the
object continues moving at constant velocity
(same speed, same direction).
2 m/s (right)
2 m/s (right)
2 m/s (right)
2 m/s (right)
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If no force is acting on an object then the
object continues moving at constant velocity
(same speed, same direction).
2 m/s (right)
2 m/s (right)
2 m/s (right)
2 m/s (right)
or
0 m/s
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If no force is acting on an object then the
object continues moving at constant velocity
(same speed, same direction).
2 m/s (right)
2 m/s (right)
2 m/s (right)
2 m/s (right)
or
or
0 m/s
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If no force is acting on an object then the
object continues moving at constant velocity
(same speed, same direction).
2 m/s (right)
2 m/s (right)
2 m/s (right)
2 m/s (right)
or
or
0 m/s
Newtons First Law of Motion