Newtons Second Law of Motion

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Newtons Second Law of Motion
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• "If the net force on an object is not zero, the
  object will accelerate. The direction of the
  acceleration is the same as the direction of the
  net force. The magnitude of the acceleration is
  directly proportional to the net force applied,
  and inversly proportional to the mass of the
  object."

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Newton's second law of motion pertains to the
behavior of objects for which all existing forces
are not balanced.

• the acceleration of an object is dependent upon
  two variables
• a) net force acting upon the object
• b) mass of the object.
• The acceleration of an object depends
• A) directly upon the net force acting upon the
  object
• B) inversely upon the mass of the object
• As the net force increases, so will the object's
  acceleration.
• As the mass of the object increases, its
  acceleration will decrease.

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Practice

• What acceleration will result when a 12-N net
  force is applied to a 3-kg object? A 6-kg object?

• 12 N 3kg x a
• A 4 m/s/s
• 12 N 6 kg x a
• A 2 m/s/s

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Practice

• 3.2 kg
• 16N m x 5 m/s/s
• 16 N/5m/s2 3.2 kg

• A net force of 16 N causes a mass to accelerate
  at the rate of 5 m/s2. Determine the mass.

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Practice

• An object is accelerating at 2 m/s2. If the net
  force is tripled and the mass of the object is
  doubled, what is the new acceleration?

• 3 m/s/s
• The original acceleration of 2 m/s/s must be
  multiplied by 3 (a and F are directly
  proportional) and divided by 2 (a and m are
  inversely proportional).

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Practice

• 12 m/s/s
• The original acceleration of 2 m/s/s must be
  multiplied by 3 (a and F are directly
  proportional) and divided by 1/2 (a and m are
  inversely proportional).

• An object is accelerating at 2 m/s2. If the net
  force is tripled and the mass of the object is
  halved, what is the new acceleration?

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Rhino and the Second Law

• http//www.ic.arizona.edu/nats101/n2.html
• Push the rhino with X N of force and determine
  the acceleration.