Question

A uniform wire of resistance R is cut into three equal pieces are joined in parallel . What is the resistance of the combination?​

Answer 1

Answer:

Resistance of a wire is directly proportional to its length. Hence, a uniform wire of resistance R is cut into 3 smaller pieces, the resistance of each of the smaller wires would be R/3.  

 

When connected in parallel  

1/Req = 1/R1 + 1/R2 + 1/R3

1/Req = 3/R + 3/R + 3/R

1/Req = 9/R

Req = R/9

Explanation:

Answer 2

Resistance of a wire is directly proportional to its length. Hence, a uniform wire of resistance R is cut into 3 smaller pieces, the resistance of each of the smaller wires would be R/3.

When connected in parallel

1/Req = 1/R1 + 1/R2 + 1/R3

1/Req = 3/R + 3/R + 3/R

1/Req = 9/R

Req = R/9