Familiar Forces
A _____ is a push or pull.
A. Gravity
B. Force
C. Magnetism
D. Friction
B. Force
Freddy and and Paul are riding bikes side by side. Paul passes Freddy. What caused Paul's bike to go faster?
Paul pushed harder on the pedals.
If the same amount of force were applied 3 balls with different masses, which would experience the greatest change in motion?
A. 40kg
B. 20kg
C. 12kg
D. 8kg
D. 8kg
Choose the three sentences that demonstrate balanced forces.
A. dog sitting still on the floor
B. book sitting on a table
C. leaf falling from a tree
D. girl bouncing a basketball
E. a boy who can't push a heavy box
A, B, & E
What is friction?
A force of resistance between two objects that touch.
You are experimenting with a little toy solider. You make a parachute and attach it with strings to the toy. When you throw it, it goes straight up and then falls straight down.
What can you do to increase the amount of time that the toy spends in the air?
Use a bigger piece of paper or plastic to make the parachute bigger.
There is 90-pound crate with a person pushing it to the right with 90N of force. Choose two amounts of force that would cause this crate to move to the right.
A. 55N
B. 80N
C. 95N
D. 50N
E. 100N
C and E
You and your friend each have a ball with the same mass. Both of you roll your balls as hard as you can and then measure the speed of each ball.
Results: your ball is exactly half as fast as the other ball. How do the forces applied to the balls differ?
Your friend used twice the force that you did.
There are two opposite forces acting on a rope, on the left side there is a net force of 400N and the right side there is a net force of 275N.
What can we say is true about the effect of the forces on the rope? Is it balanced or unbalanced and which way will the rope move?
The forces are unbalanced, and the net force on the left is stronger so it was move to the left.
What is magnetism?
The attraction and repulsion between magnetic materials.
Which BEST describes the speed of a ball as it is thrown straight up into the air and comes back down?
A. The ball goes up at a an accelerated speed, stops, then comes down at a constant speed.
B. The ball goes up at a constant speed, stops, and then it comes down at a faster speed.
C. The ball goes slower and slower as it goes up, stops, and then it comes down and continuously accelerates as it comes down.
D. The ball goes slower and slower as it goes up, stops, and then comes down at a constant speed.
C. The ball goes slower and slower as it goes up, stops, and then it comes down and continuously accelerates as it comes down.
Another way that force can cause the change in an object's motion is to...
A. change its color.
B. change its pitch.
C. change its direction.
D. change its spots.
C. change its direction.
Tim takes his sailboat on the water for two hours, and plans to stop at a dock about two hours west. He was sailing at a steady pace for the first hour. The wind speed slows by about half, and will remain that way for the second hour of his trip.
Which statement provides the BEST prediction of how the sailboat’s motion will change during the second hour?
A. It will begin going east at double the speed of the first hour.
B. It will stop moving until the boat changes directions.
C. It will decrease in speed, and its position will not change.
D. It will continue heading west at a reduced speed.
D. It will continue heading west at a reduced speed.
Mary and Ann went to some garage sales and brought their wagon with them. As they found stuff at the garage sales they added items to their wagon. They noticed that the wagon was becoming heavier. As it became heavier, it also became harder to pull. What else MOST LIKELY changed?
The speed of the wagon.
What is gravity?
The force of attraction between bodies of masses.
Mary and Ann went to some garage sales and brought their wagon with them. As they found stuff at the garage sales they added items to their wagon. All of a sudden the wagon stopped rolling and Mary could not move the wagon any further. All of the following could be the opposing force except for which one?
A. an upwards hill
B. a small breeze blew
C. a stick lodged in the axle
D. a rock getting stuck under the tire
B. a small breeze blew