Forces
What is a push or a pull called?
Force
What is the force that two surfaces exert on each other when they rub against each other?
friction
Which one has more gravity?
A. Moon
B. Earth
C. Jupiter
C. Jupiter
Because it's the biggest planet in our solar system and has the most mass
A well oiled machine machine is a type of _____________ friction.
fluid
Who would have to overcome the most friction when sledding?
A. Student One = 80 kg
B. Student Two = 75 kg
C Students Three = 60 kg
A. Student One = 80 kg
Because they have the most mass and therefore the greater mass would increase the amount of friction between the sled and the snow
Which object will require the least force to move? a mouse or a human
mouse
Because it has the least amount of mass
A smooth surface has __________ friction.
less
As the distance between two objects decreases, the gravitational force between them ____________.
a. increases
b. decreases
increases
For example: the closer you move to a planet, the greater it's gravitational pull and you will get sucked into its atmosphere
Bike tires on the road as you ride is an example of what type of friction?
Rolling friction
The amount of matter in an object is called its _________.
mass
What is the tool used to measure force that we used in lab?
Hint: you can also find them in the grocery store to measure fruit and veggies
spring scale
A rough surface needs ___________ force to overcome friction
more
How does gravity affect objects on earth?
Gravity pulls all objects toward the center of the earth
Air resistance is a type of ______ friction.
fluid
What is a valid reason that sand is poured on roads to prevent slipping:
A. It will increase frictional force
B. It will increase the coefficient of friction
C. All of the above
C. all of the above
because when roads are slippery due to ice, you want to INCREASE the friction between the ice and your tires to prevent you from crashing
All change in motion is caused by ______ _______.
Which has more friction: concrete or gym floor?
concrete
because it's not as smooth as a gym floor and therefore has more friction
The law of universal ______ states that any two objects in the universe, without exception, attract each other
Gravitation or Gravity
You must use extra force to start the motion of stationary objects. The type of friction that you must use force to overcome is called _____ friction
static
If you use a computer mouse and move it across the desk. What can be determined about the force of friction between the mouse and the desk?
A. The friction is greater than the force applied
B. The friction is less than the force applied
C. The friction is equal to the force applied
B. The friction is less than the force applied
When you have balanced forces, the net force is equal to this number
Zero
Because if the forces are equal, they cancel each other out and the net force on the object is zero and therefore doesn't move
What kind of friction allows you to walk without slipping?
Sliding friction
What are the two factors that affect the gravitational attraction between objects?
Must get both for full points*
Mass and distance
What is the phrase that means "a number that describes the degree of mechanical and molecular interaction between two surfaces"
Hint: it was a phrase we learned in the "Friction Basics" article we read as a warm up. The article is in your science folder
coefficient of friction
Which law of motion explains the scenario below?
A desk remains stationary until someone pushes it.
Newton's 1st law of motion