An ammeter of resistance 1 . 5 Ω can measure currents upto 1 A . The value of shunt resistance to measure current upto 4 A is

Step-by-step solution

Given, for an ammeter, I g = 1   A ,   R g = 1 . 5   Ω Total current, I = 4   A If R s be the shunt resistance, then according to the question circuit diagram is given, R s ‖ R g , hence have equal potential difference ) where, I g R g = I - I g R s R s = I g I - I g × R g = 1 4 - 1 × 1 . 5 = 0 . 5   Ω