Types of Forces
A push or pull on an object
What is force?
An attractive force that exists between all objects that have mass.
A force that resists the motion of two surfaces that are touching
What is friction?
Pressing the keys on a keyboard
What is a weak contact force?
Can be used to show force
What are arrows?
A push or pull on an object by another without touching it
What is a noncontact force?
The amount of matter in and object
What is mass?
Three types of friction we learned in this lesson
What are static friction, sliding friction, and fluid friction?
This causes a girl to stand on end
What is a noncontact force?
When plates in Earth's crust move, resulting in an earthquake
What is a strong contact force?
A push or pull on a object by another object that is touching it
What is a contact force?
The gravitational force exerted by another object
What is weight?
Substances that help reduce friction
What are lubricants?
The SI unit for force
What is the newton?
Prevents surfaces from sliding past each other
What is static friction?
Two traits of forces
What is strength and direction?
An object's weight is proportional to its mass
What is the relationship between mass and weight?
Swimming in the water is an example of ____ friction.
What is fluid?
The developer of the Law of Universal Gravitation
Who is Issac Newton?
Late 1600s
If you lift a pencil and drop it on the ground, this is an example of a ______. If you roll a ball across the floor with your hand, this is an example of a ______.
noncontact force; contact force
How is the gravitational force between objects affected by mass and distance?
Gravitational force increases if the mass an object increases, and decreases as the objects move apart.
When you rub soapy water on your hands, it reduces fluid friction, which is caused by this lubricant.
What is soap?
Force comes from this latin word
What is fortis?
The gravitational force between you and Earth if your mass is 45 kg
What is 440 newtons?