Contact Forces
___________________ force is The equal and opposite force pushing up against an object.
normal force
What is gravitational acceleration near Earth's surface?
9.8 m/s².
A _________________________ is a region of space where gravitational force exists at every point
gravitational field
In what units is weight measured?
Newtons
What 3 types of forces are noncontact forces?
gravity
electrical force
magnetic force
What is true of objects falling near Earth's surface when only gravity acts on them?
all objects fall with the same acceleration
How does increasing mass affect gravitational force between objects?
It increases the gravitational force.
In what units is mass measured?
kilograms
A ____________________ is A force that one object can apply to another without touching it.
noncontact force
________________ is the amount of matter in an object
mass
Which force keeps planets in orbit around the Sun?
Gravitational force
In what units is gravitational acceleration measured?
m/s2
What happens to gravitational force as distance between objects increases?
the force decreases
_____________________ is The gravitational force exerted on an object.
weight
What would happen to Earth if the Sun's gravitational force disappeared?
Earth would travel in a straight line into space
A book with a mass of 2kg is at rest on top of the desk. What is the book's weight?
19.6 N
Why don't two small objects noticeably attract each other?
Their gravitational fields are too small compared to Earth's.
What determines the strength of gravitational force between objects?
mass and distance between the objects
What is one of the difficulties astronauts experience once they have come back to Earth from being in space with less gravitational force?
A pencil with a mass of 0.0075 kg is falling toward the floor. What is the weight of the pencil?
.0735 N