Chapter 12: Electricity- Exercise- 5

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Chapter 12: Electricity

Class: X

Exercise 5

 

Question 1

Judge the equivalent resistance when the following are connected in parallel

1. 1 Ω and 10⁶ Ω
2. 1 Ω and 10³ Ω, and 106 Ω

Answer 1

 

Question 2

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 resistance of an electric iron connected to the same source that takes as much current as all three appliances, and what is the current through it?

Answer 2

Question 3

What are the advantages of connecting electrical devices in parallel with the battery instead of connecting them in series?

Answer 3

In parallel there is no division of voltage among the appliances and therefore the potential difference across each appliance is equal to the supplied voltage. Also, the total effective resistance of the circuit can be reduced by connecting electrical appliances in parallel.

 

Question 4

How can three resistors of resistances 2 Ω, 3 Ω, and 6 Ω be connected to give a total resistance of (a) 4 Ω, (b) 1 Ω?

Answer 4

 

 

Question 5

What is (a) the highest, (b) the lowest total resistance that can be secured by combinations of four coils of resistance 4 Ω, 8 Ω, 12 Ω, 24 Ω?

Answer 5