Charges
When do charges repel?
Same charge
What is current?
Charge per unit time. Amperes
I = q/t
What is a series circuit?
A circuit with one pathway for current.
What is the electrical power?
Rate of doing work
P = W/t
What are the poles called in a magnet?
North and South
When do charges attract?
Opposite charges or neutral and charged.
What is resistance?
opposition to the flow of current measured in ohms
What is a parallel circuit?
A circuit with more than one pathway for current.
What is the unit for power?
Watts
In which direction do the field lines of a magnet face?
Toward the South pole
Fe = kqq/r2
What is potential difference?
When a voltage is connected across a wire, an electric field is produced in the wire. Measured in volts
Given three 2-ohm resistors connected in series what would be the equivalent resistance.
6 ohms
Given a series circuit and a parallel circuit with the same resistors, which will use more power.
Parallel circuits will always have more current and more potential difference so more power
P = VI means brighter lights.
What is the relationship between electricity and magnetism?
Electric current creates magnetic fields.
Changing magnetic fields create a potential difference which makes current flow.
What is electric field strength?
E = F/q
What is the ohm's relationship?
V = IR
Given three, 2 ohm resistors in parallel, what would be the equivalent resistance?
2/3 ohms
If a circuit has a total current of 10 Amperes and an equivalent resistance of 2 ohms, what is its power?
P = I2R
= 102 (2) = 200 Watts
Compare a motor and a generator.
A motor converts electrical energy to mechanical energy.
A generator converts mechanical energy to electrical energy.
In what direction do field lines point?
In the direction that a positive charge would travel.
If resistance goes up when happens to current?
It decreases.
Which will have a higher current a series circuit or a parallel circuit with the same resistors?
Parallel circuits will always have more current since the equivalent resistance will be lower.
What is electrical energy?
Work
What is a electromagnetic induction?
Electric current can be produced in a wire by simply moving a magnet into or out of a wire coil.