Find the values of the following (write the formula for each and solve - 2 marks each): a. E = 200 V R = 500 Ω I =
b. R = 1 kΩ E = 100 V P =
c. P =100 W I = 5 mA E =
d. E =0.1 V I = 0.005 A R =
e. P = 50 W E = 0.5 kV I = (10 marks)

(a) What is the purpose of the power rating of a resistor? (2 marks)
(b) Current is said to be directly proportional to voltage and inversely proportional to resistance in an electrical circuit. Give examples to prove the given statement. Show all the steps/working clearly. (8 marks)
Three resistors are connected in series, A of 100Ω, B of 500Ω, and C of unknown value. The combination is connected across a 140 V supply, and the voltage across resistor A is 10 V. Calculate (a) the voltage across resistors B and C, (b) the value of resistor C, and (c) total power. (10 marks)
If the resistors in question 3 are connected in parallel across the same supply, what current would pass through each resistor and what is the total power consumed by the circuit? (8 marks)

A lamp is rated at 100W, 110V. What size resistor would you connect in series with the lamp to reduce the power to 60W? What is the power of the resistor? (8 marks)

Three resistors of 6Ω, 12Ω, and 36Ω, are connected in parallel and then connected in series to a fourth resistor of unknown value. The supply voltage is 72V and the current passing through the parallel branch is 6 A. Calculate the current through the other three resistors, the total current, the value of the unknown resistor, and the total resistance.