Question

53. Two resistances are joined in parallel, the combined resistance is 10 ohm. If one
of the resistances is 20 ohms, the value of other resistance is
(a)10 ohm (b) 15 ohm (c) 20 ohm (d ) 25 ohm ​

Answer 1

Answer:

20 ohms

Explanation:

The formula for Parallel resistance is:

1/R(net) = 1/R1 + 1/R2

Substituting the values given we get,

1/10 = 1/20 + 1/R2

=>1/R2 = 1/10-1/20

=>1/R2 = 2-1/20

=>1/R2 = 1/20

Therefore R2 = 20 ohms.