Nature of Electricity
What is the difference between DC and AC electricity?
Alternating current - current oscillates back and forth rather than flowing steadily in one direction.
What is an electrical insulator?
Give the equation for Ohm's Law as well as what each variable means.
I (current) = V (velocity) / R (resistance)
What is static electricity?
An accumulation of a large number of like charges in one place
What is electric current?
Flowing charges in a wire.
A 12-volt battery is keeping the overhead light on in the car, even though the car's engine is off. If the resistance of the overhead light bulb is 125 ohms, determine the current flowing in the circuit.
0.096 A
What makes series resistor networks different from parallel networks?
Series - all resistors are in the same loop of wire, one after the other.
Parallel - each resistor is in its own branch and the branches are connected together at the ends.
Describe the three ways static electricity can form.
Friction - electrons accumulated through rubbing
Conduction - electrons flowing in a material that is electrically conductive
Induction - a charged object comes near another object, forcing the charges in the second object to crowd together
Explain the difference between the physical reality of current in a wire and the way we handle current mathematically.
Physical reality - negative charges from toward the positive
Mathematically - positive charges from toward the negative
What voltage is required to deliver a current of 82.9 microamps to a resistance of 160 kilohm?
13.26 volts
Draw a diagram of a parallel circuit which has a battery, 3 switches, and 3 light bulbs. Draw it so that each light bulb is on a separate switch.
See board
Name and describe the two main forms of electricity.
Static electricity - when a large number of like charges accumulate in one place, giving an overall positive or negative charge to a human-scale object
Electric current - when large numbers of like charges are flowing together in some direction - inside a copper wire, for example.
A voltage of 45.4 millivolts is applied to a resistance of 27 kilohm. Determine the resulting current and state your answer in microamps.
1.69 microamps
If you are wiring a house, would series of parallel circuits be better for wiring the light?
Parallel networks so that if one light were to go out, all of the other lights won't go out. If a series network was installed, then all of the lights would go out if one went out.