F
What is gravity?
A force of attraction between two objects.
What is the definition of force?
Force is a push or pull.
Friction is....
a force that opposes motion and acts between two objects that are touching.
______________ are forces that on an object that are equal in size and opposite in direction.
Balanced forces
This can cause a change in motion....
Unbalanced forces.
A spring scale has a weight attached to it. What is the spring scale being used to measure?
Gravitational force
A spring scale is measuring the force on a block hanging from the hook. What unit would the reading on the scale be in?
Newtons!
Faris draws pictures to show Mrs. Rogers how force and motion are involved in his daily activities. Which example provides evidence that Faris is using a pulling force to affect motion?
A. Pushing a grocery cart
B. Pulling in the garbage can
C. Pushing his brother on a swing
D. Riding on his scooter
B. Pulling in the garbage can.
Kyle likes to play many types of sports. He thinks that a bowling ball requires the most force to move. Why would he think the bowling ball requires the most force?
It has the most mass.
Emma is pushing her younger sister, Avery, in her toy car. Avery gets out of the car and then her friend Julia gets into the car, who has more mass than she does. If Emma wants to make the car go the same distance that it did when she pushed Avery, what should she do?
Push the car with more force.
A rock is balanced on the side of a hill. The rock is heavy but a gentle push moves it. Explain how a small force can cause a large mass to move.
Use the words force, balance and unbalanced.
The forces on the rock were balanced, and a small additional force caused them to be unbalanced.
Paola and Leya measured the force required to hold a stapler using a spring scale. They did this on two different days. How should the results compare from the two different days?
Use word: mass, force, gravity
The mass should be the same because the mass of the stapler and the force of the gravity are the same.
Alex threw a baseball into the air and watched it go up. Then it started to fall back toward him. What force caused the baseball to start to move downward?
Gravity
Joshua wants to find out the average distance that each of his six friends can throw a ball. He asks six friends of similar sizes and ages to throw a ball as far as possible from the same starting point. Joshua notices that one friend throw the ball much farther than the other five do. He wants his results to be accurate. What should Joshua do?
Repeat the experiment two more times and find averages for each of the six throwers.
Rylan used a spring scale to life a weight and recorded a force of 6 N. Caleb lifted the same weight using a different spring scale and recorded a force of 2 N. What reasoning provides an explanation for the difference in their measurements?
A. The two results are very similar, so both measurements could be correct.
B. When different people do the same experiment, they get different results.
C. One of the spring scales was not working correctly.
D. The force of gravity changed.
C. One of the spring scales was not working correctly.
Braylen uses a stretched rubber band to propel a toy car across a flat surface. What force makes the car roll forward?
A. a push from the air
B. the pull of gravity
C. a push from Braylen's hand
D. a push from the rubber band
D. a push from the rubber band
Saniya pushes a cart with three books so it just reaches the end of a track. Next, she puts six books onto the card. Which claim explains what she must do so that the cart reaches the end of the track?
A. use less force
B. use more force
C. use the same amount of force
D. use a difference cart
B. use more force
When Ms. Williams pushes a box, a force is exerted on the box. Friction also exerts a force on the box. In what direction is the force of friction exerted?
Forward
In track and field, one event is called the shot put. Competitors throw heavy balls as far as they can. What are two things that would cause a person to be able to throw a ball farther?
A person could use a greater force by working out and building muscle, or they could use a ball with less mass.
The amount of friction exerted when an object moves across a surface depends on how the object and the surface rub together. What surface will friction be the greatest when a block of wood slides across it?
A. waxed wood
B. thick carpet
C. glass mirror
d. wet ice
B. thick carpet
Andrea pulled gently on a spring scale. The scale showed a force, but the block did not move. Why?
Use words: force, balanced
The force that she applied was balanced by another force.
Milissen and Ava are facing each other. There is a line drawn on the ground halfway between them. They are pulling on the same rope, and the rope is not moving in either direction. How would the forces need to change for Milissen to pull more of the rope over to her side of the line?
Milissen would need to pull harder or Ava would have to pull less.
Milissen and Ava are facing each other. There is a line drawn on the ground halfway between them. They are pulling on the same rope, and the rope is not moving in either direction. What can you conclude about the forces involved?
The forces are equal.
Ian was going to ride his skateboard. He pushed off the ground with his foot, and the skateboard began to move. He stopped the skateboard and was going to start again. If Ian gives a stronger push this time, how will the motion of the skateboard change compared to its motion the first time?
The skateboard will move faster and longer. The motion will increase and the stronger push increases the force acting on the skateboard.
Paola and her mother went grocery shopping on a windy day. As they entered the store, the wind pushed the cart sideways and made it hard to steer. Paola told her mother that they will not have that problem when they leave with a cart full of groceries. Explain why the cart will be easier to steer when they leave the store.
When the cart is full, its mass will be greater, which will require more force to move it. It will be harder for the wind to move it.