Vocab
A force that slows things down when two surfaces rub against each other.
Friction
Magnet pulling a paper clip
Non Contact Force
Gravity pulls objects toward the _____________ of
Earth.
Center
A student wants a toy car to move faster across the floor. What should the student do?
A. Push with less force
B. Remove all forces
C. Push with more force
D. Increase friction
C. Push with more force
Forces that are not equal and cause an object to move or change motion.
Unbalanced Forces
Pushing a shopping cart
Contact Force
Rough surfaces = ______ friction
More
A moving skateboard suddenly turns left after being pushed from the side. What happened?
A. Balanced forces kept it straight
B. An unbalanced force changed direction
C. Gravity stopped working
D. Friction disappeared
B. An unbalanced force changed direction
When an object changes position or moves from one place to another.
Motion
Gravity pulling down an apple from a tree
Non Contact Foce
When forces are balanced, there is NO change in
______________
Motion
Workers use a ramp to push a heavy box into a truck. Why does the ramp help?
A. It increases gravity
B. It reduces the force needed
C. It stops friction completely
D. It makes the box lighter
B. It reduces the force needed
When an object speeds up, slows down, stops, or changes direction.
Change in motion
Kicking a soccer ball
Contact Force
Magnetic Metals are Steel, _______, Nickel, & Cobalt
Iron
A toy car speeds up when Luis pushes it harder. What does this show about force?
A. Stronger forces can change speed
B. Forces cannot affect speed
C. Only gravity changes motion
D. Balanced forces increase speed
A. Stronger forces can change speed
The path something moves, such as left, right, up, or down.
Direction
Static Electricity making hair stand up
Non Contact Force
A force is a push or a ________.
Pull
A student slides a book more easily across a smooth table than across carpet. What explains this difference?
A. The smooth table has more friction
B. The carpet has less gravity
C. The carpet has more friction
D. The book changed mass
C. The carpet has more friction