If/, R and t are the current, resistance and time respectively, then according to Joule’s law heat produced will be proportional to_______________?

Related Mcqs:

1. The resistance of a parallel circuit consisting of two branches is 12 ohms. If the resistance of one branch is 18 ohms, what is the resistance of the other ?

   A. 18 Q B. 36 Q C. 48 Q D. 64 Q...

2. A current of 16 amperes divides between two branches in parallel of resistances 8 ohms and 12 ohms respectively. The current in each branch is_____________?

   A. 6.4 A, 6.9 A B. 6.4 A, 9.6 A C. 4.6 A, 6.9 A D. 4.6 A, 9.6 A...

3. The resistance of a conductor of diameter d and length l is R Ω. If the diameter of the conductor is halved and its length is doubled, the resistance will be

   A. R Ω B. 2R Ω C. 4R Ω D. 8R Ω...

4. The resistance of a copper wire 200 m long is 21 Q. If its thickness (diameter) is 0.44 mm, its specific resistance is around_______________?

   A. 1.2 x 10~8 Q-m B. 1.4 x 10~8 Q-m C. 1.6 x 10″”8 Q-m D. 1.8 x 10″8 Q-m...

5. Four wires of same material, the same cross-sectional area and the same length when connected in parallel give a resistance of 25 Q. If the same four wires are connected is series the effective resistance will be________?

   A. 100 Ω B. 200 Ω C. 300 Ω D. 400 Ω...

6. If a wire conductor of 0.2 ohm resistance is doubled in length, its resistance becomes______________?

   A. 0.4 ohm B. 0.6 ohm C. 0.8 ohm D. 1.0 ohm...

7. The hot resistance of the bulb’s filament is higher than its cold resistance because the temperature co-efficient of the filament is___________________?

   A. zero B. negative C. positive D. about 2 ohms per degree...

8. Copper wire of certain length and resistance is drawn out to three times its length without change in volume, the new resistance of wire becomes__________?

   A. 1/9 times B. 3 times C. 9 times D. unchanged...

9. Two copper conductors have equal length. The cross-sectional area of one conductor is four times that of the other. If the conductor having smaller cross-sectional area has a resistance of 40 ohms the resistance of other conductor will be_____________?

   A. 160 ohms B. 80 ohms C. 20 ohms D. 10 ohms...

10. Internal resistance of ideal current source is ?

    A. zero B. infinite C. finite B. 100 ohms...