A potentiometer wire has a length 2 m and resistance of `10 Omega`. It is coonnected in series with a resistance of `990 Omega` and a cell of e.m.f. 2 V. The potential gradient along the wire is

Options

A. `0.01 V//m`
B. `0.02 V//m`
C. `0.03 V//m`
D. `0.025 V//m`

Answer

A

Explanation

`I= ( E)/(R_(1)+R_(2))=(2)/(1000)=(1)/(500)A`
`therefore` P.D. across the wire `=1 R=(10)/(500)=(1)/(50)V`
`therefore " Potential gradient " =(V)/(L)=(1)/(50xx2)=0.01 V//m`