Newtons Second and Third Laws

1
Newtons Second and Third Laws
2
Newtons Second Law

• The Force applied on an object is equal to the
  mass of that object multiplied by its
  acceleration
• Simply stated, F ma
• Units of Force are Newtons
• The larger the force, the larger the acceleration
• The larger the mass, the less the acceleration

3
Newtons Third Law

• For every action, there is an equal and opposite
  reaction.
• Every time you exert a force on an object, that
  object exerts a force back on you.
• When you walk on the earth, you push down on the
  earth and it pushes back up on you.

4
The frog leaps from its resting position at the
lake's bank onto a lily pad. If the frog has a
mass of 0.5 kg and the acceleration of the leap
is 3 m/s², what is the force the frog exerts on
the lake's bank when leaping?

• A 0.2 N
• B 0.8 N
• C 1.5 N
• D 6.0 N

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The correct answer is C

• Force mass acceleration
• F .5kg 3 m/s 1.5 N

6
If you stand on a skateboard and throw a
basketball forward, which direction do you go?

• A. Forward
• B. Up
• C. Down
• D. Backward

7
The correct answer is D

• When you throw the basketball forward, you exert
  a force that pushed it forward, and it exerts a
  force that pushes you back.