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प्रश्न
How does the resistance of a wire depend on its length? Give a reason for your answer.
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उत्तर
Resistance of a wire is directly proportional to the length of the wire.
R ∝ I
The resistance of a conductor depends on the number of collisions which the electrons suffer with the fixed positive ions while moving from one end to the other end of the conductor. Obviously the number of collisions will be more in a longer conductor as compared to a shorter conductor. Therefore, a longer conductor offers more resistance.
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संबंधित प्रश्न
Two copper wires are of the same length, but one is thicker than the other. Which wire will have more resistance?
Name three factors on which resistance of a given wire depends and state how is it affected by the factors stated by you.
Assertion (A): Copper is used to make electric wires.
Reason (R): Copper has very low electrical resistance.
Resistance of a wire depends on, ______.
Exercise.
The values of current (I) flowing through a resistor for various potential differences V across the resistor are given below. What is the value of resistor?
| I (ampere) | 0.5 | 1.0 | 2.0 | 3.0 | 4.0 |
| V (volt) | 1.6 | 3.4 | 6.7 | 10.2 | 13.2 |
Resistors are connected in series if the resistance of the electric circuit is to be ______.
Three resistors are connected in series with a cell. If the current in each resistor is 1.5A, then the current through the cell will be ______.
A rheostat is also known as fixed resistance.
|
5 bulbs are connected in series in a room. One bulb is fused. It is removed and remaining 4 bulbs are again connected in series to the same circuit. What will be the effect on the following physical quantities? (Increases, Decreases, Remain Same). |
- Resistance
- Intensity of light
Observe the given circuit diagram and answer the questions that follow:
- Calculate the resistance of the circuit when the key K completes the circuit.
- Calculate the current through 3Ω resistance when the circuit is complete.
