A galvanometer has a current sensitivity of 50 microamperes. What current makes its needle read half scale?

1. Current sensitivity is the current that swings the needle right to the end of the scale. 2. Here that full-scale current is 50 microamperes. 3. Deflection is proportional to current, so half the deflection needs half the current. 4. Half of 50 microamperes is 25 microamperes. 5. Choosing 100 microamperes would drive the needle past the end of the scale rather than to its middle. _Source: OpenStax College Physics (CC BY 4.0), Ch 21 "Circuits and DC Instruments", section 21.4 DC Voltmeters and Ammeters_