Page 10 - CHAPTER-1 (Electricity)

CHAPTER 1

ELECTRICITY

Checkpoint-1

1. One ampere equals:

(A) 10 mA (B) 10 mA
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(C) 10 mA (D) 10 A

2. How many electrons passing in one second will constitute

a current of one microampere?

(A) 6.25 × 10 (B) 6.25 × 10
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12
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(C) 6.25 x 10 (D) 6.25 × 10

C. How do Charges flow?

(i) Electric Potential:

• It can be said to be the amount of work done when a positive

unit charge is moved from infinity to a point.

• If work done in moving a positive charge from infinity to a point

is , then electric potential of that point is V= W
q
• The SI unit of electric potential is given as volt (V) and is named

after Italian physicist Alessandro Volta (1745-1827). It is a scalar

quantity.

(ii) Electric Potential Difference (∆ ):

• It is defined as the work done per unit charge in moving a

positive unit charge from one point to another point.

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