Physics-DPP-1-6.Current Electricity

PHYSICS Topic: CURRENT ELECTRICITY Date: 1. When the current i is flowing through a conductor, the drift velocity is v. If 2i current is flowed through the same metal but having double the area of cross-section, then the drift velocity will be : (a) v/4 (b) v/2 (c) v (d) 4 v 2. If n, e, τ and m respectively represent the electron density, relaxation time and mass of the electron, then the resistance of a wire of length l and area of cross-section A will be : (a) ml ne2 τ A (b) mτ2A ne2l (c) ne2τA 2ml (d) ne2A 2mτ l 3. The specific resistance of a wire is ρ , its volume is 3 m3 and its resistance is 3Ω , then its length will be : (a) 3 (b) (c) ρ (d) ρ 4. The potential difference between points A and B of adjoining figure is : (a) 2 V 3 (c) 4 V 3 (b) 8 V 9 (d) 2 V 5. The reading of the ammeter as per figure shown is : (a) 1 A 8 (b) 3 A 4 (c) 1 A 2 (d) 2 A 6. The current from the battery in circuit diagram shown is (a) 1 A (b) 2 A (c) 1. 5 A (d) 3 A PHYSICS Topic: CURRENT ELECTRICITY Date: 7. In the network of resistors shown in the figure, the equivalent resistance between A and B is : (a) 54Ω (b) 18Ω (c) 36Ω (d) 9Ω 8. The figure shows currents in a part of electric circuit. The current i is : (a) 1.7 A (b) 3. 7 A (c) 1. 3 A (d) 1 A 9. The equivalent resistance and potential difference between A and B for the circuit is respectively : (a) 4Ω, 8V (b) 8Ω, 16V (c) 2Ω, 4V (d) 16 Ω, 8V 10. If VAB = – 3.5 V in the given figure, then resistance X will be : (a) 5Ω (b) 10Ω (c) 15Ω (d) 20 Ω PHYSICS Topic: CURRENT ELECTRICITY Date: Answer Key 1. (c) 2. (a) 3. (b) 4. (c) 5. (b) 6. (a) 7. (d) 8. (a) 9. (a) 10. (b)

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