Force Between Two Parallel Current - Carrying Conductors

A current carrying rectangular loop $PQRS$ is made of uniform wire. The length $PR=QS=5 \mathrm{cm} \text{and} PQ=RS=100 \mathrm{cm}$. If ammeter current reading changes from $I$ to $2I$, the ratio of magnetic forces per unit length on the wire $PQ$ due to wire $RS$ in the two cases respectively $\left(f_{PQ}^I:f_{PQ}^{2I}\right)$ is:

Two long straight wires $P$ and $Q$ carrying equal current $10 \mathrm{A}$ each were kept parallel to each other at $5 \mathrm{cm}$ distance. Magnitude of magnetic force experienced by $10 \mathrm{cm}$ length of wire $P$ is $F_{\mathit{1}}$. If distance between wires is halved and currents on them are doubled, force $F_2$ on $10 \mathrm{cm}$ length of wire $P$ will be:

A wire $X$ of length $50 \mathrm{cm}$ carrying a current of $2 \mathrm{A}$ is placed parallel to a long wire $Y$ of length $5 \mathrm{m}$. The wire $Y$ carries a current of $3 \mathrm{A}$. The distance between two wires is $5 \mathrm{cm}$ and currents flow in the same direction. The force acting on the wire $Y$ is :

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Two parallel, long wires are kept $0.20 \mathrm{m}$ apart in vacuum, each carrying current of $x \mathrm{A}$ in the same direction. If the force of attraction per meter of each wire is $2\times {10}^{-6} \mathrm{N}$, then the value of $x$ is approximately

Two $10 \mathrm{cm}$ long, straight wires, each carrying a current of $5 \mathrm{A}$ are kept parallel to each other. If each wire experienced a force of ${10}^{-5} \mathrm{N}$, then separation between the wires is _____ $\mathrm{cm}.$

A galvanometer is used in laboratory for detecting the null point in electrical experiments. If, on passing a current of $6mA$ it produces a deflection of $2°$, its figure of merit is close to :

An electrical power line, having a total resistance of $2\Omega ,$ delivers $1 \mathrm{kW}$ at $220 \mathrm{V}$. The efficiency of the transmission line is approximately :

A galvanometer of resistance $G$ is converted into a voltameter of range $0-1 \mathrm{V}$ by connecting a resistance $R$ in series with it. The additional resistance that should be connected in series with $R_1$ to increase the range of the voltmeter to $0-2\mathrm{V}$ will be :

Two wires $\mathrm{A}$ & $\mathrm{B}$ are carrying currents ${\mathrm{I}}_1$ and ${\mathrm{I}}_2$ as shown in the figure. The separation between them is $\mathrm{d}$ . A third wire $\mathrm{C}$ carrying a current $\mathrm{I}$ is to be kept parallel to them at a distance $x$ from $\mathrm{A}$ such that the net force acting on it is zero. The possible values of $x$ are:

A rigid square loop of side $\mathrm{‘}\mathrm{a}’$ and carrying current ${\mathrm{I}}_2$ is lying on a horizontal surface near a long current ${\mathrm{I}}_1$ carrying wire in the same plane as shown in figure. The net force on the loop due to the wire will be:

Two long straight parallel wires, carrying (adjustable) currents $I_1$ and $I_2$ , are kept at a distance $d$ apart. If the force $F$ between the two wires is taken as 'positive' when the wires repel each other and 'negative' when the wires attract each other, the graph showing the dependence of $F$, on the product $I_1{I}_2$ , would be:

Two long currents carrying thin wires, both with current $I$, are held by insulating threads of length L and are in equilibrium as shown in the figure, with threads making an angle ' $\theta$ ' with the vertical. If wires have a mass $\mathrm{\lambda }$ per unit length then the value of $\mathrm{I}$ is:
($g=$ gravitational acceleration)