Answer:
Voltmeter
Explanation:
A voltmeter is usually defined as an instrument that is commonly used to measure the electric potential difference acting between the two ends of a circuit. The unit of voltmeter is volts. Here, connections are made in parallel arrangement.
An ammeter is a device that is commonly used to measure the amount of flowing current within a circuit. The unit of current is in terms of amperes (A). Here, connections are made in series.
A voltmeter is usually comprised of high internal resistance in comparison to an ammeter because a high internal resistance results in the heating up of the battery and subsequent dropping its voltage and after the equipments are being cuts off, it leaves behind certain amount of energy.