Question

In an experiment the values of two resistances are measured to be r1 =( 5.0 ± 0.2 ) ohm and r2 =(10.0 ± 0.1 ) ohm. Find their combined resistance in parallel.

Answer 1

Answer:

3.33+-0.1 ohm

Explanation:

Firstly find equivalent resistance of R1 and R2 in parallel which will be 10/3=3.33ohm

for error

differentiate the equation 1/Req=1/R1+1/R2

$1 \div {req}^{2} \times d(req) = 1 \div {r1}^{2} \times \: d(r1)+ 1 \div {r2}^{2} \times d(r2)$

Now put values

req=10/3

r1=5. r2=10

d(r1)= 0.2

d(r2)=0.1

and find d(req)