as measuring the current, the shunt resistance of a galvanometer is needed to be zero. so why don't we put a wire parallel to the galvanometer a. k. a. shorted to measure the current?

Galvanometer is a device used to detect an electric current.

Explanation:

A galvanometer is an electro mechanical instrument utilized for distinguishing and demonstrating an electric flow. A galvanometer fills in as an actuator, by creating a revolving redirection, in light of electric flow moving through a loop in a consistent attractive field.

Galvanometer is a gadget which is utilized to quantify electric flows. Note that the shunt obstruction must be low with the goal that greatest current goes through the shunt. Thus galvanometer can be utilized to gauge high flows.