Unit 2.2 - Resistance Flashcards
What does the flow of charge allow us to get out?
Work
What do potential differences cause charges to do?
Flow from a higher to a lower potential
Current
How quickly charges flow
Potential difference
The difference in energy that a coulomb of charge loses between 2 points
Unit of potential difference
Volt
What does 1 volt represent?
1 Joule per coulomb, so the work done per unit charge
Equation involving potential difference
W = QV
What does W represent and what’s its unit in W = QV?
Work/energy
Joules
What does Q represent and what’s its unit in W = QV?
Charge
Coulomb
What does V represent and what’s its unit in W = QV?
Potential difference
Volts
What’s the difference between a battery and a cell?
Battery - Includes cells
Cell - 1 positive and 1 negative (long and short line)
What does the long line represent in a cell?
Positive charge
What does the short line represent in a cell?
Negative charge
What does a resistor do?
Limits/regulates the flow of electrical current in an electric circuit
What does a battery do in terms of energy in a circuit?
Increases the energy
What does a resistor do in terms of energy in a circuit?
Releases energy
What does a steeper “height” mean in terms of potential energy?
Bigger potential energy difference
What does a higher potential difference mean in terms of current?
Higher current
Why does a higher potential difference lead to a higher current?
More kinetic energy is delivered per unit charge to overcome resistance
What does closing a switch do in terms of potential difference?
Brings up the ‘dips’
No potential difference
How can we make a circuit have no potential difference?
Close the switch
What does resistance do and to what?
Slows down a current
What is Ohm’s law?
The ratio of the potential difference to the current is constant if the temperature, pressure, material, e.t.c remain constant
Equation involving resistance
R = V/I