Task 4.1 - Calculate basic electrical parameters in D.C. circuits using electrical circuit theory

A) What is the current when a charge of:

a) 3.0C passes through a lamp in 20s?

b) 3600C passes a point in 3.0 minutes?

c) 0.2μC flows through a diode in 2.0ms?

B) A charge of 4000μC passes each point in a wire in 50s. Calculate:

a) The charge in coulombs

b) The current in the wire

c) The number of electrons per second passing each point in the wire

(Electron charge = 1.6 x 10-1°C)

C)

a) What is the pd across a wire of resistance 8.00 when there is a current of 1.5A through it?

b) What is the resistance of a wire if a p.d of 6.0V drives a current of 0.25A through it?

c) A p.d of 3.0V is applied across a 150 resistor, what is the current?

D)

a) What is the power of a microwave oven that takes a current of 7.5A from a 230V supply?

b) A small 48W electric heater is connected to a 12 V supply, calculate the current.

c) When it is hot an electric bar fire has a resistance of 500. What is the power rating?

E) A lamp has a p.d of 12V across it. Calculate how much electrical energy is transferred when

a) A charge of 400C passes through it.

b) A current of 2.5A passes through it for 30s.

F) A vacuum cleaner has a rating of 460W on the 230V mains, what fuse should be fitted?