# QUESTION PAPER 9

1. a) State advantages of AC voltages over DC voltages. (5 Marks)
b) State and Explain Faradays and Lenz law of electromagnetic induction. (5 Marks)
c) Discuss the Earth as a magnet. (4 Marks)
2. a) Two branches each with 5 A current are connected across a 90 V source.
How much is the equivalent total resistance Rt. (5 Marks)
b) Three resistances are connected to form the sides of a triangle ABC.
The resistance of side AB is 40, side BC is 60 and side CA is 100.
Calculate the effective resistance between the points A and B (5 Marks)
c) A dynamo develops 10 Amp of current at 220V. What is power in KW.
(4 Marks)
3. a) What do you meant by Static electricity and how it is generated. (7 Marks)
b) Why it is important to bond and ground containers? (7 Marks)
4. a) Explain “heating effect of electric current” with suitable examples. (7 Marks)
b) What is principle of DC generator and explain its working with diagram.
(7 Marks)
5. a) In a series circuit R = 10 , XL = 15  and Xc = 25 . If the effective
current in the circuit is 5 A, calculate the power dissipation in the circuit. (7 Marks)
b) A capacitor of 20μF charged up to 500 V is connected in parallel
with another capacitor of 10 μF which is charged up to 200 V.
Determine the common potential of the capacitors. (7 Marks)
6. a) What is magnetic compass? Explain dry compass and wet card compass. (7 Marks)
b) Explain ship magnetism and its components. (7 Marks)
7. a) State the principle and describe the working of AC generator with
constructional diagram. (7 Marks)
b) An alternating voltage E = 200√2 Sin(100t)v is applied to a 2 μF
capacitor through AC ammeter. Calculate the value of current. (7 Marks)
8. Write a note on any TWO
a) Series and Shunt type DC motors (7 Marks)
b) Circular lifting magnet (7 Marks)
c) Resistance in series and parallel (7 Marks)
d) The angle of dip (7 Marks)
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