Question 1 :
Two conducting wires of the same material and of equal lengths and equal diameters are first connected in series and then parallel in a circuit across the same potential difference. What will be the ratio of heat produced in series and parallel combinations?

Question 4 :
In a schematic diagram of a circuit consisting of a battery of three cells of 2 V each, a 5 ohm resistor, a 8 ohm resistor and a 12 ohm resistor and a plug key, all connected in series and put an ammeter to measure the current through the resistors and a voltmeter to measure the potential difference across 12 ohm resistor. What will be the equivalent resistance?

Question 5 :
The resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?

Question 6 :
A current of 1 A is drawn by a filament of an electric bulb. Number of electrons passing through a cross section of the filament in 16 seconds would be roughly

Question 7 :
A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistance, which may be used separately, in series, or in parallel. What is the current when the two coils are used in series?

Question 8 :
Which uses more energy, a 250 W TV set in 1 hr, or a 1200 W toaster in 10 minutes?

Question 9 :
An electric lamp of 100 ohm, a toaster of 50 ohm and a water filter of resistance 500 ohm are connected in parallel to a 220 V source. What is the resistance of an electric iron connected to the same source that takes as much current as all the three appliances ?

Question 10 :
In a schematic diagram of a circuit consisting of a battery of three cells of 2 V each, a 5 ohm resistor, a 8 ohm resistor and a 12 ohm resistor and a plug key, all connected in series and put an ammeter to measure the current through the resistors and a voltmeter to measure the potential difference across 12 ohm resistor. What will be the readings in voltmeter?

Question 11 :
Which instrument is used to measure electric current in a circuit?

Question 12 :
An electric motor takes 5 A from a 220 V line. What is the power of the motor?

Question 13 :
An electric lamp of 100 Ω, a toaster of resistance 50 Ω, and a water filter of resistance 500 Ω are connected in parallel to a 220 V source. What is the current through the electric iron if it is connected to the same source that and takes as much current as all three appliances?

Question 14 :
An electric bulb is rated 220 V and 100 W. What will be the power consumed if it is operated on 110V?

Question 15 :
When a 12 V battery is connected across an unknown resistor, there is a current of 2.5 mA in the circuit. Find the value of the resistance of the resistor.

Question 16 :
Several electric bulbs designed to be used on a 220 V electric supply line, are rated 10 W. How many lamps can be connected in parallel with each other across the two wires of 220 V line if the maximum allowable current is 5 A?

Question 18 :
An electric kettle consumes 1 kW of electric power when operated at 220 V . A fuse wire of what rating must be used for it ?

Question 19 :
What is the equivalent resistance when 1Ω ,10$^{6}$Ω and $10^{3}$Ω are connected in parallel?