Embibe Experts Solutions for Chapter: Current Electricity, Exercise 1: Rajasthan Board-2020

In given diagram value of carbon resistor is $22\times {10}^5\mathrm{\Omega }\pm 5\%$. Write colour of first ring $\mathrm{A}$.

Calculate the value of unknown resistance $\mathrm{R}$ in given circuit. If wheatstone bridge is in balanced condition.

Derive formula for obtaining internal resistance of a primary cell with help of potentiometer. Draw circuit diagram.

Explain the method of find unknown resistance with the help of meter bridge. Draw circuit diagram.

Why do we get balancing point in the middle of the meter bridge generally?

Draw a circuit diagram for comparison of $\mathrm{emf}$ of two primary cells with the help of potentiometer.

Three resistors are connected in parallel. The electric current $7.5 \mathrm{A}$ is flowing in this combination from a battery of $\mathrm{emf} 30 \mathrm{V}$. If the values of two resistors are $10\mathrm{\Omega }$ and $12\mathrm{\Omega }$, then find the value of third resistor.

Write Kirchhoff's second law.