Balance Basics
When the wind blows, my sculpture moves in many different directions, but it does not fall. Is my sculpture still balanced?
Yes, balanced sculptures won't fall down!
What do we call the spot where an object balances?
The balance point.
What happens when two like sides of magnets face each other?
They repel, push apart.
Any example is acceptable.
Push (repel) and pull (attract)
A still sculpture.
If the balance point is in the middle, where should you place your objects to keep the sculpture balanced?
What happens when unlike sides of magnets face each other?
They attract, pull together.
What non-contact force causes a balloon to make your hair stick up?
Static Electricity.
What makes sculptures move?
A force causes a sculpture to move.
Two students push a box with equal force in opposite directions. Are the forces balanced or unbalanced?
Balanced, the box will not move because they are pushing with the same force.
By adding more objects to the shorter side or to the side that keeps going up. If we add more force to this side, it won't fly up, it will balance with the other side.
My magnet does not lift my paperclip unless I touch the magnet to the paperclip, but I want it to float without touching. What should I do?
Add more magnets to increase the force.
Two objects with the same type of electric charge are brought near each other. What will they do?
They will repel. Like sides/Like electric charge repel.
A toy car is at rest. Two students push it equally hard in opposite directions. Will it start moving because of their pushes?
No, it will not move.
A soccer ball is sitting still. One student kicks it, and it starts moving. What caused the ball to move?
A force (push) from the student.
I want my sculpture to spin in circles when the wind blows, what kind of balance point should I use?
A round balance point.
My friend and I each have a magnet, she takes 10 steps away from me, but our magnets won't attract. What can we do so that the magnets pull to each other?
Move closer. Less distance = stronger force
Can a magnet pull a magnetic object from across a piece of paper without touching it? What type of force is this?
Yes, attracting/non-contact force.
A student pushes a box harder than another student pushes it in the opposite direction. Are the forces balanced or unbalanced?
The forces are unbalanced because it will move more in a different direction.
A book rests on a table without moving. Are the forces on the book balanced or unbalanced?
The upward normal force from the table balances the downward gravitational pull on the book, keeping it at rest.
I want my sculpture to seesaw when people apply force to it, what kind of balance point should I use?
A triangle balance point.
A contact force is when two objects move each other by touching. A non-contact force is when objects move each other WITHOUT touching.
A charged balloon attracts a small piece of paper. A student says, “The balloon must be touching the paper for a force to act.” Explain why the student is wrong, and name another non-contact force that can make objects move.
The balloon can attract the paper without touching it because static electric force acts at a distance. Magnetic force is another non-contact force.
A soccer ball rolls across the floor and eventually stops. What force causes the ball to slow down as it rolls?
Friction.