1 ohm resistance is in series with a Ammeter which is balanced by 75 cm of potentiometer wire. A standard cell of 1.02 V is balanced by 50 cm.t he ammeter shows a reading of 1.5 A. The error in the ammeter reading is

Options

A. 0.002 A
B. 0.03 A `P_(1)` to `P_(2)`
C. 1.01 A
D. no error

Answer

B

Explanation

`(V_(1))/(V_(2))=(l_(1))/(l_(2))=(75)/(50)impliesV_(1)=1.53V`
`I_(1)=(V_(1))/(I)=1.53A`, error `=1.53-1.50=0.03`