PRIME MINISTER’S OFFICE-REGIONAL ADMINISTRATION AND LOCAL GOVERNMENT  
PHYSICS FORM TWO  
CURRENT ELECTRICITY TEST O1  
TIME: 1:30 HRS  
YEAR 2026  
Instrucꢀons  
Answer ALL Questions  
1. (a) What is the benefit of using circuit breaker rather than a fuse?  
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(b) An electrician wants to replace a fault fuse with a normal piece of conducting wire. should  
you let him? Why or why not?  
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(c) State the defects of a simple cell and explain how these defects can be minimized  
i.  
Defects of a simple cell  
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Ways to minimized defects in simple cell.  
ii.  
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2. (a)Explain the properties of fuse  
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(b)Explain the function of fuse  
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(c)How does a fuse in a lighting circuit differ from that in a heating or power circuit?  
(d)What is the importance of using a fuse in an electrical appliance  
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3. (a) A refrigerator is marked 250V, 400W.calculate the maximum current that can flow through  
it  
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(b) Discuss what might happen to the refrigerator if it is connected to a supply of:  
i.  
280V  
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ii.  
110V.  
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4. (a) why are the electrical appliances earthed?  
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(b) Explain the precautions to take during electrical wiring of a house.  
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(c) Describe how electricity from a fuse box is distributed to other parts of a house.  
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5. (a) Explain briefly why most plugs have three pins  
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(b) In three pin -plug, we find wires labelled N, L, and E:  
a) What do these letters mean?  
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b) At present, what is the internationally accepted colour for wires labelled N, L and E?  
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6. (a) Give the differences between the tree system and ring system methods of wiring a house.  
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(b) Why is the earthed thicker and longer in a three-pin plug?  
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(c) Mention two devices used for checking electrical faults in domestic appliances  
i.  
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ii.  
7. (a) If a lamp on a 240V supply draws a current of 0.25A, calculate the power the uses to  
transfer electrical energy into heat and light energy.  
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(b) A television set (TV) rated 40W is switched ON for 5 hours every day.  
a. How much electrical energy in kWh does this TV consume in 30 days?  
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b. If the price of a unit of electricity is Tsh 229.60, what is the total electricity cost of  
watching this TV in 30 days?  
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8. (a)A bulb draws a current of 0.5A from a 240V source. Calculate the energy dissipated in 10  
minutes.  
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(b)A resistor of 100Ω is connected across a battery of 12V.How much heat is dissipated across  
the resistor in 5s? (Ignore the internal resistance of the battery)  
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(c) The balance length of a potentiometer wire for a cell of e.m.f , E1=1.63V is 85cm.If the cell  
is replaced by another one of e.m.f, E2=1.07V, calculate the new balance length.  
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9. (a) Differentiate between pd and current.  
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(b) Show diagrammatically how an ammeter is connected to measure current of the resistor,  
R.  
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(c) Draw the circuit diagram to show how a voltmeter is used to measure the pd of load R.  
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10. (a) Define the following terms  
i.  
Electric current  
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ii.  
Resistance  
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iii.  
Voltage  
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(b) convert these currents into ampere  
i. 500µA  
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ii.  
250µA  
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(c) The current travelling through the filament of a lamp is 2A. How many electrons pass  
through the filament in one second?  
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