Question

If $400\Omega$ of resistance is made by adding four $100\Omega$ resistance of tolerance $5\%$, then the tolerance of the combination is?

• A. $15\%$
• B. $20\%$
• C. $5\%$
• D. $10\%$

Answer 1

Answer: (C)

$5\%$

Given that,

Resistance of all resistors is $R=100\Omega$

Tolerance, $T=5$%

Tolerance for the combination of resistors is given by:

$T=\frac{R_1{T}_1+R_2{T}_2+R_3{T}_3+R_4{T}_4}{R_1+R_2+R_3+R_4}$

$T=\frac{100\times 5\times 4}{400}$

$T=5$%