Newton’s Laws of Motion

Dynamic dynamics and unexpected returns

Sir Isaac Newton

• Determined many physical laws based on mathematics.

• His book, Principia, revolutionized the fields of both science and mathematics

• He did a great job of explaining effects that seemed to have no causes

Newton’s First Law of Motion

• Inertia• An object at rest will remain at

rest, and• an object in motion will remain in

motion unless• acted upon by an outside force

– Dependent on mass– Inherent property of matter

Newton’s Second Law of Motion

• Force equals mass multiplied by acceleration

• F = m•a– Force is any push or pull that can

affect motion– Mass in kg, acceleration in m/s2

– Newtons: 1N = 1kg•m/s2

What would the net force be if two players kick a soccer ball from opposite directions according to the diagram?

0%0%0%0%1

2

3

4

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30 31 32

1. 60 N, to the left2. 60 N, to the right3. 0 N4. 180 N, upwards

Newton’s Third Law of Motion

• For every action, there is an equal and opposite reaction– These forces act on two different

objects, so they are not balanced forces

The Big “Mo”

• Momentum is the product of an object’s mass multiplied by its acceleration.

• p = m • v• kg•m/s = kg • m/s

Law of Conservation of Momentum

• Momentum can not be created or destroyed under normal circumstances

• Momentum can be changed from one form to another– Total momentum before a change must

equal total momentum after a change• Ex. truck of gravel coming to a stop,

pieces of a dropped light bulb

Law of Conservation of Momentum

• Formulam1v1+m2v1 = m1v2+m2v2