What is a long thin piece of material such as a wire, or a string that is wounded into circles?
a. current b. brushes c. coil
d. armature e. magnet
c. coil
How many types of magnets are there?
3
1.temporary and 2.permanent magnets, 3. electromagnets
Which one of the following is not used in making an electromagnet?
a. bolt b. battery c. wire
d. paper clips e. feather
e. feather
True or False?
All electric motors use magnets or electromagnets.
True
Which type of car has less maintenance? (p. 9)
a. electric car
b. gasoline-powered car
a. electric car
Circuit is a flow of _______________________.
a. water b. electrons c. gas d. air
b. electrons
The area surrounding a magnet is called a magnetic ______________.
field
True or False?
-->An electromagnet is a permanent magnet and its electricity cannot be turned off.
False
Which one of the following does not have electric motors?
a. blender b. washing machine d. dryer
e. computer f. electric toaster g. refrigerator
f. electric toaster
Why people said electric vehicles are the wave of the future?
Your answer.
Which component could cause the electric motor to rotate continuously? (p. 4)
a. commutator b. circuits c. rotor d. armature
a. commutator
True or False?
The earth core has its own magnetic field.
True
Increasing the amount of coils around the bolt will make the magnet become ____________________.
stronger
What is the metal loop winded in the electric motor?
a. brushes b. stator c. commutator d. armature
d. armature
Complete the following sentence.
--> An e-motor car may get cheaper and cheaper in the future since (because) _________________________________________.
Your answer.
What happens when two south poles of a magnet are near each other?
They repel, or push apart, each other.
When using 1.5 Volts battery in the electromagnet experiment, can you think any other way to change the strength of an electromagnet to pick up more paperclips?
Use 6 Volts battery instead, or more wires (coils, solenoids螺線管)
**The more turns of wire your magnet has, the better. Keep in mind that the further the wire is from the core, the less effective it will be.
Which component could cause the electric motor to rotate continuously?
a. commutator b. circuits c. rotor d. armature
commutator
Complete the sentence.
--> If you need to use a hairdryer in the bathroom, ________________________.
Your answer.
(** avoid using it it near the water / sinks / baths / toilets)