Checkpoint
Earth’s Forces
Dr. Browne
Check Point
1. What is a force? A _________ or __________
2. To describe a force both the _______________ and
the ________________ are needed.
3. Unbalanced forces occur when . . .
4. Balanced forces are ______________ in size and
________________ in direction.
5. _______________ forces do not cause a change in an
objects motion.
6. The _________________ of an object is the amount of gravity
pulling on it.
7. Look at the diagram below and answer the question that
follow:
3 N
10 N
9N
a. What is the net force acting on the box? ________
b. Draw the resultant vector:
8. The Gravity is the force of ___________________ between objects
in the universe.
9. What is Universal gravitation? Who came up with it?
10. If the mass of an object increases, gravity will _______________.
An object with less mass will have _______________ gravity than
an object with greater mass.
11. As the distance between objects increases, the gravity will
_____________________.
12. The measure of the pull of gravity on an object is known as
_________________. ( ___ = m x g)
13. As gravity changes, an objects _____ will change, but its _____
will not change.
14. A spring scale is used to measure ____________, now
label the missing parts of the spring scale below:
:
a. __________
b. __________
c. __________
d. __________
The Coal Family:
15. Friction moves in the _______________________ direction of
motion.
16. The friction of an object at rest is called _________________
friction.
17. The friction of two solid surfaces moving over each other is called
________________ friction.
18. The friction of wheels is an example ____________ friction.
19. The friction caused by moving through liquids and gases is called
_____________ friction.
20. Friction is affected by ________________ and how
______________ they are pushed together.
21. To reduce friction a ______________________ is used.
22. The amount of force applied to a specific area is known as
___________________.
23. The pressure caused by the force exerted by Earth’s
atmosphere is called _______________________.
24. To calculate pressure you would use the formula: _______
25. The SI units of pressure are: ___________________
26. To change or manipulate pressure two factors are considered:
__________________ and/or ____________________
27. Both gases and liquids exert pressure, this is known as
_______________ pressure.
28. It is the ___________________ in gases and liquids bumping
into _________________ that cause the pressure.
29. A ______ is an object that travels around another object.
30. The ____ is an example of a natural satellite. An artificial
satellites has been launched into space to gather ____.
31. A satellite that has a higher orbit will take ___ to travel
around Earth than lower orbiting satellites.
32. Orbits are created by _____ and ____ which pull on the
object, causing it to travel in an _____ path between the two
forces.
Answer Key
Answer Key
1. What is a force? A PUSH or PULL
2.
To describe a force both the MAGNITUDE (SIZE) and
the DIRECTION are needed.
3. Unbalanced forces occur when FORCES ARE
UNEQUAL IN SIZE. Net Force < 1N and causes a
change in motion.
4. Balanced forces are EQUAL in size and OPPOSITE in
direction.
5. BALANCED forces do not cause a change in an objects
motion.
6. The WEIGHT of an object is the amount of gravity pulling on
it.
7. Look at the diagram below and answer the question that
follow:
3 N
10 N
9N
a. What is the net force acting on the box? [2 N, Left]
b. Draw the resultant vector:
2N
8. The Gravity is the force of ATTRACTION between objects in the
universe.
9. What is Universal gravitation? NEWTON’S LAW OF GRAVITY THAT
STATES THAT ALL OBJECTS IN THE UNIVERSE ARE
AFFECTED BY GRAVITY. Who came up with it? ISAAC NEWTON
10. If the mass of an object increases, gravity will INCREASE. An object
with less mass will have LESS gravity than an object with greater mass.
11. As the distance between objects increases, the gravity will DECREASE.
12. The measure of the pull of gravity on an object is known as WEIGHT. (
W = m x g)
13. As gravity changes, an objects WEIGHT will change, but its MASS will
not change.
14. A spring scale is used to measure FORCE, now label
the missing parts of the spring scale below:
:
a. POINTER
b. SCALE
c. SPRING
d. MASS
15. Friction moves in the OPPOSITE direction of motion.
16. The friction of an object at rest is called STATIC friction.
17. The friction of two solid surfaces moving over each other is called
SLIDING friction.
18. The friction of wheels is an example ROLLING friction.
19. The friction caused by moving through liquids and gases is called
FLUID friction.
20. Friction is affected by SURFACES and how HARD they are
pushed together.
21. To reduce friction a LUBRICANT is used.
22. The amount of force applied to a specific area is known as
PRESSURE.
23. The pressure caused by the force exerted by Earth’s
atmosphere is called AIR PRESSURE.
24. To calculate pressure you would use the formula: P = F / A
25. The SI units of pressure are: PASCAL (Pa)
26. To change or manipulate pressure two factors are considered:
AMOUNT OF FORCE and/or SURFACE AREA
27. Both gases and liquids exert pressure, this is known as FLUID
pressure.
28. It is the MOLECULES in gases and liquids bumping into
SURFACES that cause the pressure.
29. A SATELLITE is an object that travels around another
object.
30. The MOON is an example of a natural satellite. An
artificial satellites has been launched into space to gather
DATA.
31. A satellite that has a higher orbit will take LONGER to
travel around Earth than lower orbiting satellites.
32. Orbits are created by FORWARD MOTION and
GRAVITY which pull on the object, causing it to travel in an
ELLIPTICAL path between the two forces.