Define gravity
a noncontact force that pulls objects downward pulling towards the center of the earth
Give an example of unequal forces.
You kick a soccer ball and the soccer ball moves.
Define Friction
What unit do we measure force in? What tool can you use to measure force?
Newtons
Spring scale
When playing hockey on ice, what force causes the puck to stop?
Friction
Give an example of equal forces.
Pushing on a brick wall and it doesn't move.
When golfing, what force causes the ball to come to a stop?
Friction
What force is always pulling everything towards the Earth's core?
Gravity
Give an example of equal forces.
Ms. Weeks bowling ball is sitting on the floor not moving.
Ms. Weeks and Ms. Herrera are moving furniture in the classroom. They are pushing on a bookshelf together but it won't move. Don't worry, they are so strong! They take a breath, push again, and it moves! Explain how this is possible.
The teachers pushed with more force the second time which made unequal forces and made the bookshelf move. Our teachers are so cool.
The kitties are playing on the rug. The big kitty passes the ball to the fuzzy kitty. The ball stops half way though. What force stopped the ball?
Friction of the carpet stopped the ball from moving.
EX: playing pool you hit the cue ball which applies unequal forces to the other balls. It looses energy of motion and the other balls gain energy of motion.
Explain what equal forces are. Give an example.
Equal forces are when 2 forces are equal in force (newtons) and in opposite directions. There is NO MOTION in equal forces.
An example is Ms. Weeks pushing against the wall and nothing moves.
Another example is a book sitting on a table. Gravity pulls the book down, the table pushes up on the book. Nothing moves.
The plant is hanging from a rope on the ceiling. The plant is not moving. What forces are acting on the plant? What direction are the forces pulling? Are they equal or unequal?

Gravity pulls the plant down while the rope pulls it upward. The forces are equal, there is no motion.
You have a paper airplane you are flying. The paper airplane starts to fall. What forces are acting on it?
The force of gravity is stronger than the upward force of the paper airplane flying.
Ms. Weeks and Mrs. Herrera go play put-put-golf together. They decide to to an investigation to test how applying more force to the golf ball affects the distance and speed it travels. What is your hypotheses?
We predict that as more force is applied to the golf ball, the distance and speed will increase. because the golf ball will receive more energy.
Describe what energy transfers occur when you are bowling.
When bowling, the person transfers mechanical energy to the bowling ball, then the bowling ball transfers that mechanical energy to the bowling pins. This causes the pins to fall over!
When we did the toy car investigation where we tested the steepness of the ramp (the height of the ramp). What happened when the ramp got steeper?
The friction decreased
The weight of the toy car stayed the same
The car traveled faster and farther
In our balloon investigation we tested application of force that made the balloon travel along the string. What was the variable we changed to get the balloon to travel farther?
We added more air to the balloon, filling it up all the way to make it larger.