Vocabulary
One kind of force that works over a distance without touching is _______.
Magnetism
Balanced
What is a force?
A) Type of energy
B) Push or Pull
C) Kind of motion
D) Type of machine
B) Push or Pull
Gravity is a force that ______.
A) Pushes objects upward
B) Pulls objects toward Earth
C) Makes objects lighter
D) Stops motion completely
B) Pulls objects toward Earth
True or False:
Tile flooring has more friction than carpet.
False.
Carpet has more friction than tile, glass, and ice.
You can _____ a friend on a swing, and you can _____ on a rope during tug-a-war. Both are types of forces.
Push/Pull
When you use the brakes on a bike to come to a quick stop, the force that causes the wheel to stop moving is ________.
Friction
What is an example of a pull?
A) Kicking a ball
B) Pushing a door open
C) Pulling a wagon
D) Throwing a ball
C) Pulling a wagon
What happens when forces are unbalanced?
A) Nothing changes
B) The objects stay still
C) The objects motion changes
D) The object becomes heavier
C) The objects motion changes
True or False:
When you rub your hands together, they produce heat from friction.
True.
Remember, when you rub your hands together for a long time, your hands feel warm!
Motion
Friction requires objects to be in ________, or touching.
Contact
What happens when forces are balanced?
A) The object moves faster
B) The object changes direction
C) The object does not move
D) The object disappears
C) The object does not move
What does friction do?
A) Speeds objects up
B) Changes color
C) Opposes motion
D) Makes objects float
C) Opposes motion
True or False:
A pattern of motion is a random movement that we cannot predict.
False.
A pattern of motion is a movement that repeats and can be predicted.
You can ______ what will happen to objects undergoing repeating motion by studying patterns.
Predict
You have two bar magnets. The magnetic poles that are the same will _______, and the opposite magnetic poles will _______.
Repel/Attract
What is motion?
A) A force that pushes objects
B) A change in position
C) A type of energy
D) A tool used by engineers
B) A change in position
What is a contact force?
A) A force that works from far away
B) A force between touching objects
C) A force that only works in air
D) A force that only pulls
B) A force between touching objects
True or False:
Plastic is more likely to be attracted to a magnet than iron.
False.
Things such as plastic and wood are not magnetic. Iron is more likely to be attracted to a magnet.
Lubricant
When you jump, why do you move upward?
A) Gravity disappears
B) Your muscles create an unbalanced force
C) The ground stops pushing
D) Air pushes you down
B) Your muscles create an unbalanced force
Why do engineers use lubricants like oil?
A) To increase friction
B) To reduce friction
C) To stop motion
D) To add weight
B) To reduce friction
True or False:
When two of the same poles of a magnet face each other, they repel against each other.
True.
Same poles repel, opposite poles attract!