Question

a potential difference V= (20+-1)is applied across a resistance R= equal to (8 +-2 )ohm find the current with limits of error .

Answer 1

v=IR
=>I=V/R
=>dI/I=VdR-RdV/R²=20×2-8×1/8²=32/64=0.5



the answer is 0.5

Answer 2

V = IR

error always gets add up hence it would be +-3

I = V/R = 20/8 =2.5 ampere

so answer is 2.5 +-3 ampere