Page 43 - CHAPTER-1 (Electricity)

CHAPTER 1

ELECTRICITY

Checkpoint-8

1. A cable of resistance 10 carries electric power from a generator

producing 250 kW at 10000 volt. The current in the cable is

(a) 25 A (b) 250 A

(c) 100 A (d) 1000 A

2. In the above question, the power lost in the cable during

transmission is

(a)12.5 kW (b)6.25 kW

(c)25 kW (d) 3.15 kW

Mental floss!

If a heating coil of resistance R, (length l) consumed power P, when

voltage V is applied to it then by keeping V constant if it is cut in n

equal parts, then the resistance of each part will be R/n and from

1
P consumed ∝ , power consumed by each part P'=nP.
R

Checkpoint-9

Question 1

What is the heating effect of electric current?

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