Question

What is the highest lowest total resistance that can be obtained by combination of four coils of resistance 4 ohm 8 ohm 10 ohm and 20 Ohm

Answer 1

Answer:

The highest resistance is secured when all the four coils connected in the series .

in that case

R=4+8+12+24

= 48 ohms

The lowest resistance is secured win all the four coils are connected in parallel

In that case,

1/R= 1/4 + 1/8 + 1/12 + 1/48

=12/24

R = 24/12

R = 2 ohms