Current
Current is the flow of what?
Electrons
Can current flow in an incomplete circuit?
No
What is potential difference?
Driving force to move electrically-charged particles
What is resistance?
Anything that slows flow of a current.
What is static electricity?
Electrical charge that stays in one place
What tool is used to measure electrical current, and how is it placed in a circuit?
An ammeter; wired in series with point of interest
What is a circuit diagram?
Simplified drawing of components of a real circuit
What are the units of potential difference?
Volts
What is the difference between a conductor and an insulator?
Conductors pass current easily, while insulators do not
Two positively-charged objects come near. Will they be pushed toward or away from the other?
Away
In parallel circuits current has a choice of what?
Routes back to the beginning of the circuit
What happens if there is a break in a series circuit?
The entire circuit stops operating
What job does a battery do in a circuit?
Provides force to push charges around a circuit
Component A has resistance of 3Ω, Comp B has 0.5Ω, and Comp C has 0.01Ω. Which is the best electrical conductor?
Component C
What is a magnetic field?
Region where magnetic materials experience a force
A series circuit has 3 bulbs. A current of 3A passes through the first bulb. What current passes through the third bulb?
3A
What type of circuit allows part of the circuit to be switched off?
A parallel circuit
What instrument is used to measure potential difference, and how is it connected to a circuit?
Voltmeter, connected in parallel around point of interest
A 24V battery is able to push 1.5A of current through a large bulb. What is the resistance of the bulb?
20Ω
Which direction do magnetic field lines point?
Away from magnetic north, toward magnetic south
What direction do magnetic field lines point near a wire carrying a current?
Counter-clockwise circles
Draw a wire in the shape of a solenoid
It should look like a spring or coil
What happens if you raise the potential difference between two ends of an oper circuit too high?
Why is "soft" iron used in electromagnet cores?
Demagnetizes quickly when the current is turned off
Explain how a simple electric motor works
A loop of coiled wire is placed in a magnetic field. When current moves through the wire, its magnetic field interacts with the field of the magnets. Forces on either end of the wire push in opposite directions, causing the wire to spin.