Advertisements
Advertisements
प्रश्न
Name three factors on which resistance of a given wire depends and state how is it affected by the factors stated by you.
Advertisements
उत्तर
The following factors can affect a wire's resistance:
- Length of wire: The resistance increases as the wire length increases. R ∝ (l) (directly proportional).
- Area of cross-section (a): The area of the cross-section has an inverse relationship with resistance. For example, the resistance of a thick wire is lower than that of a thin one.
- Temperature (T): As the temperature rises, the resistance of the wire also rises.
APPEARS IN
संबंधित प्रश्न
How does the resistance of a wire depend on its radius? Explain your answer.
How does the resistance of a wire depend on its length? Give a reason for your answer.
Assertion (A): Copper is used to make electric wires.
Reason (R): Copper has very low electrical resistance.
How are the home appliances connected in general, in series or parallel. Give reasons.
The effective resistance of three resistors connected in series is lesser than the lowest of the individual resistances.
Two conductors of resistance 2 R and R are connected in series in a battery circuit. The ratio of heat developed In them is ______.
______ is the only non-metal that is a good conductor of electricity.
Match the following:
| Column I | Column II | ||
| 1. | Resistor | a. | Galvanometer |
| 2. | Connecting wire | b. | Voltmeter |
| 3. | Current in an electric circuit | c. | Copper |
| 4. | Potential difference | d. | Constantan |
Define the following:
Variable resistor
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.
