Lakhmir Singh and Manjit Kaur Solutions for Chapter: Electricity, Exercise 13: Long Answer Type Questions

(a) What is the ratio of potential difference and current known as?
(b) The values of potential difference $V$ applied across a resistor and the corresponding values of current $I$ flowing in the resistor are given below:
Potential difference, $V$ (in $\mathrm{volts}$): $2.5 5.0 10.0 15.0 20.0 25.0$
Current, $I$ (in $\mathrm{amperes}$):              $0.1 0.2 0.4 0.6 0.8 1.0$
Plot a graph between $V$ and $I,$ and calculate the resistance of the resistor.
(c) Name the law which is illustrated by the above $V-I$ graph.
(d) Write down the formula which states the relation between potential difference, current and resistance.
(e) The potential difference between the terminals of an electric iron is $240 \mathrm{V}$, and the current is $5.0 \mathrm{A}$. What is the resistance of the electric iron?