Review: Day 1

Who is Isaac Newton?

Let’s Explore …Forces and Motion Simulation

Review

• A force is a push or a pull from one object to another. The direction of the force is indicated by an arrow. Forces are measured in Newton’s (N).

F

Balanced Forces• When two forces are equal there is no movement on

the object and it is considered “ balanced”.• The net force between the two objects is zero.

Fnet=0• Objects that are at rest are balanced. There are

equal forces at play. (book on table, sitting in a chair.) • Objects that are in constant motion are also

considered balanced until another force acts upon it. (Girl on skateboard with no friction)

Let’s Explore Again…Forces and Motion Simulation

Unbalanced Forces

• Objects that experience two unbalanced forces result in motion.

• What happens when you put two people on the left side of the rope and one on the right?

• What happens when you put one large person and two small people pulling at the opposite ends of the rope?

Newton’s First Law• An object at rest stays at rest and an object in motion stays in

motion with the same speed and in the same direction unless acted upon by an unbalanced force.

http://www.bbc.co.uk/history/historic_figures/newton_isaac.shtml

Let’s explore…

Explore Newton’s Second Law

• Using a force of 100 N, have the robot push the little girl on the skateboard. Notice her speed.

• Now, have the robot push the father with the same force. What do you notice about his speed? Is it faster, slower?

• Now, let’s turn on the Mass button and experiment with different masses. What can we conclude?

Newton’s Second Law

<http://www.bbc.

co.uk/history/

hisoric_figures/

newton_isaac.shtm>

l

• The unbalanced force on an object is equal to the mass of the object multiplied by it’s acceleration.

What is Acceleration?

Friction• Friction is a force that occurs when two substances

meet. Let’s experiment with changing the friction from rough to slippery.

• What do you notice?