CBSE Test paper Chapter- Electricity-01 Fm: 27 Time: 45 min. One mark questions 1. Define the term "electric current”. 2. Define the term „resistivity‟ of a material. 3. How is a Voltmeter connected in the circuit to measure the potential difference between two points? 4. You have two metallic wires of resistances 6 ohm and 3 ohm. How will you connect these wires to get the effective resistance of 2 ohm? 5. If the distance between two electric charges is doubled, how much will the force exerting between them change to? Two marks questions 6. State Ohm‟s law. "The resistance of a conductor is 1Ω.” What is meant by this statement? 7. Why are coils of electric toaster made of an alloy rather than a pure metal? 8. Why is the series arrangement not used for domestic circuits? 9. A wire of resistivity „ρ‟ is stretched to double its length. How does it affect the (a) resistance (b) resistivity? 10. Write 2 points of difference between direct and alternate current 3 marks questions 11. Derive the equation for resultant resistance of Resistors in series 12. How much work is done in moving a charge of 3 coulumb from a point at the volts 115 to a point at 125 volts?[ 30j] 13. A heater wire whose power is 4KW is connected to 220 V source calculate:- (i) Electric current in the circuit (ii) Resistance of heater (iii) Energy consumed in 2 hours. 14. (a) Which has more resistance: 100W bulb or 60W bulb? (b) A wire of resistance 5 ohm is bent in the form of a closed circle. What is the effective resistance between the two points at the end of any diameter of the circle?
14. (a) Which has more resistance: 100W bulb or 60W bulb?