List of top Physics Questions on Current electricity asked in COMEDK UGET

A battery of emf 10 volts and internal resistance 3 \(\Omega\) is connected to a resistor. If the current in the circuit is 0.5 A, what is the resistance of the resistor?

A parallel combination of 'n' cells of emf 'E' and internal resistance each, are connected across the external resistance 'R'. If the external resistance 'R' is negligibly small, then the current 'I' through the external resistance is:

Find the current through the $40\text{ }\Omega$ resistor in the given circuit containing an ideal diode, three resistors, and two cells.

A galvanometer of resistance $50\text{ }\Omega$ has $30$ divisions and a current sensitivity of $1\text{ mA/div}$. What should be the shunt resistance so that it can be converted into an ammeter of range $10\text{ A}$?

A student measures the terminal potential difference \( V \) of a cell of emf \( \varepsilon \) and internal resistance \( r \) as a function of the current \( I \) flowing through it. Which of the following graphs will give the values of emf \( \varepsilon \) and internal resistance \( r \)?

A galvanometer having a resistance of \(50\Omega\) is shunted by a wire of resistance \(10\Omega\). If the total current is \(2\,\text{A}\), the current passing through the shunt is:

Two wires A and B made of same material having length 10 cm and 40 cm respectively are connected in parallel to the same source of emf 10 V. What will be the ratio of the drift velocity of the electrons in the wire A to the drift velocity in the wire B?

A galvanometer of \( 50\Omega \) resistance is converted into an ammeter using a shunt resistance of \( 10\Omega \). If the same resistance is used to convert the same galvanometer into a voltmeter, what would be the ratio of the resistance of the ammeter to the resistance of the voltmeter?

Ten cells, each having internal resistance \( 1\Omega \) and emf \( 1.5 \, V \) are connected in series. But unknowingly 3 cells are connected wrongly in series. The effective internal resistance and emf of the series combination are respectively:

The wire made of Phosphor bronze is used as the suspension strip in the moving coil galvanometer, because:

The resistance of a wire is \(5\,ohm\) at \(25^\circ C\) and \(7\,ohm\) at \(100^\circ C\). The resistance of the wire at \(0^\circ C\) is

Two identical conductors of lengths \(l\) and \(3l\) respectively are maintained at the same temperature. They are given potential differences in the ratio \(1:3\). The ratio of their drift velocities is

A bulb of resistance \(280\,\Omega\) is supplied with a voltage \(V = 400\sin \pi t\). The peak current is

A student measures the terminal potential difference \(V\) of a cell (emf \(\varepsilon\) and internal resistance \(r\)) as a function of current \(I\) flowing through it, and draws \(V\) versus \(I\) graph. The slope and intercept of the graph respectively are

The resistance of the galvanometer and shunt of an ammeter are 90 ohms and 10 ohms respectively, then the fraction of the main current passing through the galvanometer and the shunt respectively are:

Silicon doped with arsenic is

A uniform wire of resistance $R$, of the radius $r$ is uniformly drawn until its radius is reduced to $r/ n$, Its new resistance is

A wire of resistance $9 \Omega$ is uniformly stretched such that.its radius becomes $1/3$ of the original radius. Ratio of the new to old resistance is

The resistance of mercury at $4.2 \, K$ is

A DC source of $30 \, V$ is connected across two resistors of $200\, \Omega$ each connected in series. A voltmeter of resistance $200 \, \Omega$ is connected across a resistor. It reads

$A, B$ and $C$ are three voltmeters of resistances $4000 \, \Omega , 6000 \Omega$ and $12000 \Omega$. When a potential difference? is applied between $X$ and $Y$, voltmeter readings are $V_A, V_B$ and $V_C$. Then

The resistance of a metallic conductor increases with temperature because