Force and Motion
What force keeps you from floating off into space?
Gravity
We have learned about three different waves. Which of the following is NOT a type of wave?
a. (water) waves
b. sound waves
c. starry waves
d. light waves
c. starry waves
What are the two ends of a magnet called?
north pole and south pole
How many different forms can water have?
a. one
b. two
c. three
d. four
c. three
True or False
Simple machines really are simple. They don't do the work for us.
Which is the correct definition of a force?
a. energy that stops movement
b. a push or a pull
c. a pull
d. a push
b. a push or a pull
a. amplitude
b. reflection
c. vibration
b. reflection
True or False
Electrons cause charges and CANNOT be seen.
True!
All things we touch are made of __________.
a. energy
b. force
c. matter
d. solids
c. matter
How is a wedge and inclined plane similar AND different?
The wedge and inclined plane are both slanted. They look similar in appearance.
The wedge and inclined plane are used differently. The inclined plane is used to move something from here to there, but a wedge is used to pull apart.
Balanced
When forces are balanced, the same amount of force is put on the object, causing it to remain still.
Which wave(s) can we NOT see?
sound waves and light waves
Electric forces happen between electric charges. What are the names of the two charges?
positive charge and negative charge
Each kind of matter has its own special properties. Properties are how we tell what something is like. Which of the following is NOT a property?
a. is blue
b. is hard
c. has energy
c. has energy
Pretty much everything is matter, except energy!
What kind of simple machine is a knife?
A wedge
You kick a football and it flies from one end of the field to the other. What does this tell you about the force?
The forces are unbalanced.
The kick (push) is stronger than the pull, causing the football to move.
If you a stretch a rubber band between your thumbs and ask someone to pluck it, you will hear a sound. You will also see the rubber band moving back and forth so fast it is just a blur. What is that back and forth motion called?
vibration
Fill in the blank.
Electricity that goes through wires is called _______________ electricity.
current
All matter has ____________ and takes up space.
(hint: not weight)
mass
A seesaw is an example of which type of simple machines?
Lever
A skydiver jumps from an airplane. Two forces act on her as she falls. One is gravity. What is the other force that slows her fall?
(hint: two words)
air resistance
Waves carry ___________ from one place to another.
a. energy
b. vibration
c. air
d. light
a. energy
If you rub a rubber balloon on wool cloth, it can stick to the wall or ceiling. Explain what causes the balloon to stick?
(hint: electrons)
When you rub a balloon with wool, it picks up extra electrons. It now has negative charge. It sticks because the wall has positive charge.
(Just like the ends of a magnet, positive charge connects to negative charge)
List the three forms of water.
1.
2.
3.
liquid, solid, gas (water vapor)
List all six simple machines.
1. inclined plane
2. wedge
3. screw
4. lever
5. wheel and axle
6. pulley