# Physics1 Defining Forces in Physics

The word force has lots of meanings. Most of them have nothing to do with physics. How are forces in physics defined?

The block is sitting not moving on the table. Is a force acting on it?

Question: What are forces in physics?

Materials:

Block of wood

Table

Wire with a crook at the end

Procedure:

Set the block of wood on the table

Observe the block for a minute

Push on the block

Pushing on the block made it move across the table. Pushing is another kind of force.

Use the wire with the crook to pull the block

Push the block off the edge of the table

Observations:

What the block of wood does sitting on the table:

What the block does when you push on it:

What the block does when you pull on it:

What the block does when you hit the table:

What the block does when you push it off the table:

Conclusions:

What makes the block move?

Is a force acting on the block as it sits on the table?

Why doesn’t the block move because of this force?

How do you know a force is acting on the block?

How does a force act?

How do you think forces in physics are defined?

I forgot to grab my wire to pull the block across the table. Fingers do work to apply force by pulling.

What I Found Out:

My block of wood did not move sitting on the table. It only moved when I pushed or pulled it.

A force is working on the block as it sits on the table. When the block is pushed off the table this force pulls it to the floor. The only reason the force couldn’t move the block before is because the table was in the way.

A force acts by pushes and pulls.

What Are Forces in Physics?

Physics defines force as a push or a pull. There are many kinds of forces but they all act by pushing of pulling to move an object.

Can you think of some other kinds of force?

Gravity is one. It pulls objects down to the ground.

Magnets have force. They can be used to push or pull each other around.

Electricity especially static is a force. Think about what happens when you rub a balloon and touch it to a wall.

For the next fourteen physics projects we will look at physical forces, pushing and pulling and how we can use this through simple machines to make work easier.