The I-V graph shown in the figure is plotted for the different wires of the same material and of equal cross-sectional area. Which of the wire is longest among them?

P

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Q

No worries! We‘ve got your back. Try BYJU‘S free classes today!

R

No worries! We‘ve got your back. Try BYJU‘S free classes today!

S

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Open in App

Solution

The correct option is D $S$
By Ohm’s law,
$V = I R$
$\frac{1}{R} = \frac{I}{V}$
The slope of I-V graph is equal to reciprocal of resistance.
Hence, slope of I-V graph, $m = \frac{1}{R}$
From the graph, $m_{P} > m_{Q} > m_{R} > m_{S}$
$⟹ R_{P} < R_{Q} < R_{R} < R_{S}$

Resistance of a substance is given by:
$R = ρ \frac{l}{A}$
where:
$ρ$ is the resistivity, $A$ is the cross sectional area and $l$ is the length.

Given, all the wires are of same material and same cross-section area, hence $ρ$ and $A$ are constant.
$⟹ R \propto l$
Since, wire $S$ has the highest resistance, it is the longest wire.

Suggest Corrections

Similar questions

Q. A point mass

m

is suspended using two wires of different material as shown in the figure. If cross-section area of wire

- 1

and wire

- 2

are

3 m m^{2}

and

\sqrt 3 m m^{2}

respectively, which of the following is correct?

Q. The V-I graph of the four wires made of different materials of equal length and thickness was plotted. Which among the following materials will produce the V-I graph of the least slope?

Q. Three wires A,B, C made of the same material and radius have different lengths. The graphs in the figure shows the elongation-load variation. The longest wire is:

The V-I graph for four different wires of different materials having the same length and diameter are shown in the figure. Which one of the following wire has the highest resistivity?

Q. Three elastic wires,

P Q, P R

and

P S

support a body

P

of mass

M

, as shown in the figure. The wires. are of the same material and cross-sectional area, the middle one being vertical. The load carried by the middle wire is:

Join BYJU'S Learning Program