The error in measuring the curent with tangent galvanometer is minimum when the deflection is about

Tangent galvanometer measure

Tangent galvanometer is used to measure

Tangent galvanometer is used to measure

Show that percentage error in the measurement of m/B by a deflection magnetometer is minimum when deflection is near about 45^(@) .

In the figure, galvanometer G gives maximum deflection when

In the figure, galvanometer G gives maximum deflection when