The circuit shown here is used to compare the emf of two cells $E_1$ and $E_2 (E_1 > E_2)$. The null point is at $C$ when the galvanometer is connected to $E_1$. When the galvanometer is connected to $E_2$, the null point will be
Ato the left of $C$
Bto the right of $C$
Cat $C$ itself
D
no change in null point
Easy
Download our app for free and get started
Ato the left of $C$
a In case of potentiometer, $\mathrm{E}_{1} / \mathrm{E}_{2}=l_{1} / l_{2} .$ As given that $\mathrm{E}_{1}>\mathrm{E}_{2},$ therefore $l_{1}>l_{2} .$ Therefore, the null point for the cell of $\mathrm{emf}$ $\mathrm{E}_{2}$ must be at shortest length than that of cell $\mathrm{E}_{1} .$ Thus, the null point on potentiometer wire should shift towards left of $\mathrm{C}$
Download our app
and get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
If in the circuit shown below, the internal resistance of the battery is $1.5$ $\Omega$ and $V_P$ and $V_Q$ are the potentials at $P$ and $Q$ respectively, what is the potential difference between the points $P$ and $Q$
The length of a given cylindrical wire is increased to double of its original length. The percentage increase in the resistance of the wire will be..... $\%$.
In the given figure of meter bridge experiment, the balancing length $AC$ corresponding to null deflection of the galvanometer is $40\,cm$. The balancing length, if the radius of the wire $AB$ is doubled, will be $....cm$
An electric toaster has resistance of $60\ \Omega$ at room temperature $\left(27^{\circ} \mathrm{C}\right)$. The toaster is connected to a $220 \mathrm{~V}$ supply. If the current flowing through it reaches $2.75 \mathrm{~A}$, the temperature attained by toaster is around : (if $\alpha=2 \times 10^{-4} /{ }^{\circ} \mathrm{C}$ )
A potentiometer wire of length $10 \,m$ and resistance$20 \,\Omega$ is connected in series with a $25 \,V$ battery and an external resistance $30\, \Omega$. A cell of emf $E$ in secondary circuit is balanced by $250\, cm$ long potentiometer wire. The value of $E$ (in volt) is $\frac{x}{10}$. The value of $x$ is.......
Two resistors of resistance, $100\,\Omega$ and $200\,\Omega$ are connected in parallel in an electrical circuit. The ratio of the thermal energy developed in $100\,\Omega$ to that in $200\,\Omega$ in a given time is: