An electric kettle operates at 230V and draws a current of 13A. What would the equivalent current be at the following voltages used in the UK National Grid? Show all your working.
a) 33kV (33000V) (4 marks)
b) 400kV (4 marks)
Power used: 230*13
Current used= 230*13/33,000
To find the equivalent current at different voltages, we can use the formula:
I = P / V
Where I is the current, P is the power, and V is the voltage.
Given that the electric kettle operates at 230V and draws a current of 13A, we can first find the power using the formula:
P = V * I
P = 230V * 13A
P = 2990W
a) 33kV (33,000V):
Using the formula I = P / V, we can calculate the equivalent current at 33kV.
I = 2990W / 33,000V
I ≈ 0.0906A
b) 400kV:
Using the formula I = P / V, we can calculate the equivalent current at 400kV.
I = 2990W / 400,000V
I = 0.0075A
Therefore, the equivalent current at 33kV is approximately 0.0906A, and the equivalent current at 400kV is 0.0075A.