Topic 2: Electricity

Question 1

what is the voltage in a series circuit?

Answer 1

shared amongst components
V(total) = V(1) + V(2) + V(3)

Question 2

what is the current in a series circuit?

Answer 2

the current is constant in all parts
I(1) = I(2) = I(3)

Question 3

what is the resistance in a series circuit?

Answer 3

the resistance is the sum of the individual resistances of components
R(total) = R(1) + R(2) + R(3)

Question 4

what is the voltage in parallel circuits?

Answer 4

all components get the full voltage
V(total) = V(1) + V(2) + V(3)

Question 5

what is the current in a parallel circuit?

Answer 5

the current is split between branches based on resistance
I(total) = I(1) + I(2) + I(3)

Question 6

what is the resistance in parallel circuits?

Answer 6

reciprocal of total resistance is the sum of the reciprocals of the individual resistances

Question 7

how to investigate the current in resistor at constant temperature varied with the potential difference across the resistor

Answer 7

• measure the current using an ammeter
• measure the potential difference using a voltmeter
• vary the resistance of the variable resistor
• record a range of values of current and potential difference
• ensure the current is low to avoid temperature increase
• reverse connect of R to power supply
• repeat measurements of I and V in negative direction
• plot a graph of current against potential difference