An ammeter `A` of finite resistance, and a resistor `R` are joined in series to an ideal cell `C`. A potentiometer `P` is joined in parallel to `R`. The ammeter reading is `I_(0)` and the potentiometer reading is `V_(0)`. `P` is now replaced by a voltmeter of finite resistance. The ammeter reading now is `I` and the voltmeter reading is `V`.

Options

A. `I gt I_(0), V lt V_(0)`
B. `I gt I_(0), V gt V_(0)`
C. `I = I_(0), V lt V_(0)`
D. `I lt I_(0), V gt V_(0)`

Answer

A

Explanation

(a) effective resistance of `R` and `V` is less than effective resistance of `R` and `P`, hence p.d. across voltmeter (or `R`) is less than previous value.
Also overall resistance decreases, so overall current increases, hence reading of ammeter increases.