Embibe Experts Solutions for Chapter: Electric Current, Exercise 1: Exercise

State Ohm's law. Suggest an experiment to verify it and explain the procedure.

Ohm's law is valid only for metal conductors provided the temperature and other physical conditions remain constant. Why?

What are the limitations of Ohm's law?

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

An electric heater draws a current of $5 \mathrm{A}$ when connected to $220 \mathrm{V}$ mains. Calculate the resistance of its filament.

Define non-ohmic materials and give examples.

Calculate the amount of electric current flowing through the body of a person who touches the live wire of $240 \mathrm{V}$ with dry fingers. Assume that the resistance of the person's body is $100000 \mathrm{\Omega }$.

Deduce the expression for equivalent resistance for three resistors connected in series.