The portal has been deactivated. Please contact your portal admin.

Question Video: Finding the Current through Components in Series Physics • 9th Grade

The circuit in the diagram consists of two resistors in series, with ammeters 𝐴₁, 𝐴₂, and 𝐴₃ placed at different points in the circuit. 𝐴₁ reads 4 A. What is the current given by the second ammeter 𝐴₂? What is the current given by the third ammeter 𝐴₃?

02:20

Video Transcript

The circuit in the diagram consists of two resistors in series, with ammeters 𝐴 one, 𝐴 two, and 𝐴 three placed at different points in the circuit. 𝐴 one reads four amps. What is the current given by the second ammeter 𝐴 two? What is the current given by the third ammeter 𝐴 three?

Okay, so this question is about a series circuit, which is a circuit that consists of just one loop for the charges to flow around. We can recall that in a series circuit, the current is the same at all points in that circuit. The reason for this is that since the circuit consists of a single loop, all the charges have to follow the same path. In other words, all the charges that flow through here also flow through here and here and here and so on. This means that there is the same number of charges per second passing each point in the circuit. And since current is charge per unit time, this means that there must be the same current at every point.

We’re told in the question that the ammeter 𝐴 one reads a current of four amps. So we know that there must be a current of four amps at this point in the circuit. In the first part of the question, we’re asked to find the current given by the ammeter 𝐴 two. So that’s this ammeter here in our diagram. Since we know that for a series circuit like the one in our diagram, the current is the same at all points in that circuit and we know that the current at another point in the circuit has a value of four amps, then we know that the current at the position of the ammeter 𝐴 two must also be four amps.

So our answer to this first part of the question is that the current that will be measured by the ammeter 𝐴 two is equal to four amps.

The second part of the question asks for the current given by the ammeter 𝐴 three. So in the circuit diagram, that’s this ammeter here. As before, we know that the current must have the same value at all points in this series circuit. So the current at the position of ammeter 𝐴 three must also be four amps. And so our answer to the second part of the question is that the current given by the ammeter 𝐴 three will be equal to four amps.

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.