Lesson 9 - Resistance Flashcards
What does the word ‘resistance’ mean?
It means to oppose.
What unit is resistance measured in?
Ohms
What does the current in the circuit that is flowing depend on?
It depends on the voltage and resistance
How can resistance be calculated?
It can be calculated if you divide voltage by current
What does the formula triangle of voltage, resistance and current look like? (Show the units/signs including their full forms)
It has V (voltage) on top and R (resistance) and I (current) at the bottom.
Do good electrical conductors have a low resistance or a high resistance?
Low resistance.
How is resistance caused? (Hint: it’s got something to do with electrons)
Electrons collide with other atoms as they move which causes resistance.
Why do insulators have less current?
It is because the electrons are so packed together in the substance/material.
What is resistance in a metal caused by?
It is caused by the collision of free electrons and metal ions.
Why are metals good conductors? (Hint: something to do with electrons)
They have many free electrons that can move when voltage is applied.
True or false.
Resistance does NOT depend on the type of material and object it is made of.
False
If you manage to make a wire much thinner, how will that increase resistance?
Thinner wires have less space for charges to move.
True or false.
Low resistance material have many free electrons.
True
What is resistance the measure of?
It is the measure of the opposition to current flow in an electric circuit.
