**The values of current I flowing in a given resistor for the corresponding values of potential difference V across the resistor are given below –**

I (Ampere) |
0.5 | 1.0 | 2.0 | 3.0 | 4.0 |

V (Volts) |
1.6 | 3.4 | 6.7 | 10.2 | 13.2 |

**Plot a graph between V and I and calculate the resistance of that resistor**.

Asked by Vishal kumar | 1 year ago | 243

The plot between voltage and current is known as IV characteristic. The current is plotted in the y-axis, while the voltage is plotted in the x-axis. The different values of current for different values of voltage are given in the table. The I and V characteristics for the given resistor is shown below.

The slope of the line gives the value of resistance.

The slope can be calculated as follows:

Slope = 1/R = BC/AC = 2/6.8

To calculate R,

R = 6.8/2 = 3.4 Ω

The resistance of the resistor is 3.4 Ω

Answered by Shivani Kumari | 1 year ago**Explain the following.**

**a.** Why is the tungsten used almost exclusively for filament of electric lamps?

**b. **Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?

**c.** Why is the series arrangement not used for domestic circuits?

**d.** How does the resistance of a wire vary with its area of cross-section?

**e.** Why copper and aluminum wires are usually employed for electricity transmission?

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**(i) **a 6 V battery in series with 1 Ω and 2 Ω resistors, and

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