Topic 2 - Resistance

Question 1

what is the formula for voltage?

Answer 1

voltage = current x resistance

Question 2

what does the gradient determine on a current-voltage graph?

Answer 2

the resistance

Question 3

what happens if the gradient becomes steeper on a current-voltage graph?

Answer 3

the resistance is lowering

Question 4

what happens to the current through a wire (constant temp) when you vary the voltage?

Answer 4

current is directly proportional to the voltage

Question 5

what happens to the current through different resistors (constant temp) when you vary the voltage?

Answer 5

current is directly proportional to the voltage. different resistors have different resistances so there are different slopes on a current-voltage graph

Question 6

what happens to the current through a metal filament lamp when you vary the voltage?

Answer 6

as temp increases, resistance increases

Question 7

what happens to the current through a diode when you vary the voltage?

Answer 7

current only flows in one direction