Ontario Grade 9 Science Class Practice Exam 2026 – Your Complete Guide to Exam Success!

A voltmeter is a device used to measure the potential difference (voltage) between two points in an electrical circuit. It is incorrect to state that the function of a voltmeter is to measure current, resistance, or capacitance because those are different measurements that require different instruments. In summary, the function of a voltmeter is specifically to measure potential difference, making option B the correct answer.