Two wires of same metal have the same length | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) The resistance of a wire is given by $R = \rho \frac{L}{A}$.Since the wires are of the same material and length,$R \propto \frac{1}{A}$.Given the

Vedclass · Accepted Answer

$40$

Vedclass · Answer

(A) The resistance of a wire is given by $R = ho \frac{L}{A}$.Since the wires are of the same material and length,$R \propto \frac{1}{A}$.Given the ratio of cross-sectional areas is $A_1 : A_2 = 3 : 1$,where $A_1$ is the thicker wire and $A_2$ is the thinner wire.Therefore,the ratio of resistances is $\frac{R_1}{R_2} = \frac{A_2}{A_1} = \frac{1}{3}$,which implies $R_2 = 3R_1$.Given the resistance of the thicker wire $R_1 = 10\,\Omega$.Thus,the resistance of the thinner wire $R_2 = 3 	imes 10 = 30\,\Omega$.When joined in series,the total resistance $R_{eq} = R_1 + R_2 = 10 + 30 = 40\,\Omega$.

Two wires of same metal have the same length but their cross-sections are in the ratio $3:1$. They are joined in series. The resistance of the thicker wire is $10\,\Omega$. The total resistance of the combination will be ............. $\Omega$.

Similar Questions

Different combinations of $3$ resistors of equal resistance $R$ are shown in the figures. The increasing order for power dissipation is:

In the given figure,$R_1=10 \Omega, R_2=8 \Omega, R_3=4 \Omega$ and $R_4=8 \Omega$. The battery is ideal with an emf of $12 \text{ V}$. Find the equivalent resistance of the circuit and the current supplied by the battery.

Two metal wires of identical dimensions are connected in series. If $\sigma_1$ and $\sigma_2$ are the conductivities of the metal wires respectively,the effective conductivity of the combination is

You are given $10$ resistors each of resistance $2 \ \Omega$. First,they are connected to obtain the possible minimum resistance. Then,they are connected to obtain the possible maximum resistance. The ratio of maximum and minimum resistance is . . . . . . .

Find the effective resistance between $A$ and $B$ in the given circuit.

Vedclass Test Series

Exam Paper Generator

Online Exam Module