Video Transcript
The diagram shows an electric
circuit. Which component of the circuit is
the voltmeter measuring the potential difference across?
In this question, we are given a
diagram of an electric circuit with five components: a power cell, a motor, a bulb,
a buzzer, and a voltmeter. We want to find which component the
voltmeter is measuring a potential difference across. A voltmeter is a device that can
measure the potential difference across two points in a circuit and subsequently any
component between those points.
Recall that when we attach a
voltmeter to a circuit, it must be done in parallel, with both ends of the voltmeter
attached to two different points along the wire of the circuit, so it can measure
the potential difference between the points. So, in order to find which
component the voltmeter is measuring a potential difference across, we simply have
to determine which component is in between these two points. Looking at the circuit, we can see
that the voltmeter is attached on either side of the buzzer.
Therefore, the component of the
circuit which the voltmeter is measuring the potential difference across is the
buzzer.