Embibe Experts Solutions for Chapter: Current Electricity, Exercise 2: Exercise-2

A circuit consists of five identical conductors as shown in figure. The two similar conductors are added as indicated by dotted lines. The ratio of resistances before and after addition will be

A galvanometer has resistance of $400 \mathrm{\Omega }$ and deflects full scale for current of $0.2 \mathrm{mA}$ through it. The shunt resistance required to convert it into $3 \mathrm{A}$ ammeter is

The value of current $l$ in the circuit will be

There is a voltameter in a circuit. In order to triple its range, the resistance of how much value should be used?

A wire is bent in the form of a triangle, what will be the equivalent resistance between its one end and the mid point of the side is

A Wheatstone Bridge' circuit has been set up as shown. The resistor $R_4$ is an ideal carbon. The resistor $R_4$ is an ideal carbon resistance (tolerance $=0\%$) having bands of colours black, yellow and brown marked on it. The galvanometer, in this circuit, would show a 'null point' when another ideal carbon resistance $X$ is connected across $R_4,$ having bänds of colours

Assertion : The current density $\overrightarrow{J}$ at any point in ohmic resistor is in direction of electric field $\overrightarrow{E}$ at that point.

Reason : A point charge when released from rest in a region having only electrostatic field always moves along electric lines of force.

Assertion : In the following circuit emf is $2 \mathrm{V}$ , internal resistance of the cell is $1 \mathrm{\Omega }$ and $R=1 \mathrm{\Omega }$ Then reading of the voltmeter is $1 \mathrm{V}$$.$

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Reason : $V=E-ir, i=\frac{2}{2}=1 \mathrm{A}$ and $r=1 \mathrm{\Omega }$