If the resistance of each edge of a cube shaped wire frame as shown in figure below is R, then the resistance between points 1 and 7 is

Options

A. `(5R)/(6)`
B. `R/6`
C. `5R`
D. `6/5 R `

Answer

A

Explanation

Now , we apply kirchhoff.s loo[ rule in the darkened path
`sum V = 0 = (-I)/(3) R- I/6 R - I/3 R + V " or " V = IR (5/6)`
But ` V = IR_(eq)`
` IR_(eq) = IR (5/6) " or " R_(eq) = 5/6 R`