Ohm’s Law Flashcards
State ohms law;
The current through a conductor is directly proportional to the potential difference across the conductor at a constant temperature.
What 2 things must exist between two points for charge to flow?
1] a voltage
2] a conductor
What do we call conductors that resist the flow of charge?
Resistors
Is it true that depending on the resistance of the circuit, the same battery will deliver different currents?
Yes, true.
What is a rheostat?
A resistor whose resistance can be changed.
In which circuit [series or parallel] is the current Constance/the same everywhere.
In a SERIES circuit.
What does the slope [gradient] represent on a graph derived from the formula r = v/I
It represents the resistance.
What happens to a RESISTOR and the RESISTANCE as current flows?
- the resistor heats up
- increase the resistance
Therefore the resistance will not remain constant in a wire.
Name 4 factors on which the resistance of a conductor is dependent and how do each of these affect the resistance of the conductor? [8]
1] length - the longer the conductor the HIGHER the resistance.
2] thickness - the thicker the conductor, the LOWER the resistance.
3] temperature - the higher the temperature, the HIGHER the resistance.
4] types - different types of conductors have different resistances.
On a set of axes [graph] which wire would have the greatest resistance?
The wire with the greatest slope will have the greatest resistance.
What factors affect resistance? [4]
1] type of wire
2] thickness of wire; the THICKER the conductor, the LOWER the resistance.
3] temperature; higher temperature = higher resistance
4] length; longer the conductor = higher resistance.
Give the definition off the ohm;
A conductor has a resistance of 1 ohm if the current is 1 ampere when a potential difference of 1 volt is maintained between its ends.
What happens to the resistance if you add resistors in a series circuit?
Greater resistance [large amount of resistance]
What happens to the resistance when you add resistors in a parallel circuit?
Lower resistance/ small amount of resistance.
Resistors in SERIES are [what] dividers.
[voltage]
