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प्रश्न
What are the advantages of connecting electrical devices in parallel with the battery instead of connecting them in series?
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उत्तर
There is no division of voltage among the appliances when connected in parallel. The potential difference across each appliance is equal to the supplied voltage. The total effective resistance of the circuit can be reduced by connecting electrical appliances in parallel.
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संबंधित प्रश्न
A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistances, which may be used separately, in series, or in parallel. What are the currents in the three cases?
The equivalent resistance of the parallel combination of two resistors of 60Ω and 40Ω is _______.
A) 24Ω
(B) 100Ω
(C) 50 Ω
(D) 240Ω
Show how would you join three resistors, each of resistance 9 Ω so that the equivalent resistance of the combination is
1) 13.5
2) 6 Ω
Which of the following arrangement, A or B, has the lower combined resistance?

A wire that has resistance R is cut into two equal pieces. The two parts are joined in parallel. What is the resistance of the combination?
Explain with diagram what is meant by the "series combination" and "parallel combination" of resistances. In which case the resultant resistance is : (i) less, and (ii) more, than either of the individual resistances?
In the circuit given below:
(a) What is the combined resistance?
(b) What is the p.d. across the combined resistor?
(c) What is the p.d. across the 3 Ω resistor?
(d) What is the current in the 3 Ω resistor?
(e) What is the current in the 6 Ω resistor?
A 4 Ω coil and a 2 Ω coil are connected in parallel. What is their combined resistance? A total current of 3 A passes through the coils. What current passes through the 2 Ω coil?
How will you connect three resistors of resistances 2 Ω, 3 Ω, and 6 Ω to obtain a total resistance of 4 Ω, and 1 Ω?
Four resistors each of resistance 2Ω are connected in parallel. What is the effective resistance?
You have three resistors of values 2Ω, 3Ω and 5Ω. How will you join them so that the total resistance is less than 1Ω? Draw diagram and find the total resistance.
In the following figure calculate:
- the total resistance of the circuit
- the value of R, and
- the current flowing in R.

Explain, why is the p.d. between the terminals of a storage battery less when it is supplying current than when it is on open circuit. A battery of e.m.f. 10 volts and internal resistance 2.5 ohms has two resistances of 50 ohms each connected to it. Calculate the power dissipated in each resistance
(a) When they are in series,
(b) When they are in parallel.
In each case calculate the power dissipated in the battery.
A cell supplies a current of 1.2 A through two 2Ω resistors connected in parallel. When the resistors are connected in series, if supplies a current of 0.4 A. Calculate the internal resistance and e.m.f of the cell.
An electrical appliance has a rating 100 W, 120V. The resistance of element of appliance when in use:
Three resistors of 6Ω, 4Ω and 4Ω are connected together so that the total resistance is 8Ω. Draw a diagram to show this arrangement and give reason to justify your answer.
A piece of wire of resistance R is cut into three equal parts. These parts are then connected in parallel. If the equivalent resistance of this parallel combination is R1, what is the value of the ratio R1 : R?
Study the following circuit:

On the basis of this circuit, answer the following questions:
i. Find the value of total resistance between the points A and B.
ii. Find the resistance between the points B and C.
iii. Calculate the current drawn from the battery, when the key is closed
OR
iii. In the above circuit, the 16Ω resistor or the parallel combination of two resistors of 8 Ω, which one of the two will have more potential difference across its two ends? Justify your answer.
Four resistors each of resistance 5 Ω are connected in parallel. What is the effective resistance?
You have three resistors of values 2 Ω, 3 Ω, and 5 Ω. How will you join them so that the total resistance is less than 1 Ω? Draw a diagram and find the total resistance.
