Practise questions based on chapter 9 (current electricity ) for class 9

 1. A charge of 3.2 × 10-³ C is moved between two points and 6.4 joule of work is done. What is the potential difference between the two points?

2. The  magnitude of charge of an electron is 1.602 × 10-¹⁹ C . How many electron charges make ten coulomb?

3. A Steady Current of 10 ampere flows through a circuit for 30 minutes. How much charge has circulated through the circuit in this time?

4. If 'I' is the current through a wire and 'e' is the charge of electron, then find the number of electrons in 't' seconds ?

5. Ravi wants to measure current in a resistance present in a circuit. How should he connect the ammeter in the circuit?

6. Name the class of a substance which had infinitely high electrical resistance?

7. What constitutes current in a metal wire? Distinguish between a resistor and rheostat.

8. How much work is done in moving a charge of two coulombs from a point at 108 V to a point at 138 volts?

9. What is a circuit? Draw an electrical circuit diagram in which various components are two cells, key,rheostat,bulb,voltmeter and ammeter.

10. Why does the filament of an electric bulb in an electric circuit gets white hot, but not the connecting wires? State four factors on which the resistance of a wire depends. Explain how does the resistance depend on the factors mentioned by you?