Question

In (figure 1), what is the magnitude of the current in the wire above the junction?.

Answer 1

The magnitude of the current in the wire above the junction is;

5 A

Calculations using Kirchoff's Current Rule

From the image of the circuit attached, we see that;

For wire 1, current is flowing towards the junction and that;

Resistance; R₁ = 2Ω

Voltage; V₁ = 6V

For wire 2, current is flowing towards the junction and that;

Resistance; R₂ = 5 Ω

Voltage; V₂ = 10 V

Formula for current is;

I = V/R

Thus;

I₁ = V₁/R₁

I₁ = 6/2

I₁ = 3 A

I₂ = V₂/R₂

I₂ = 10/5

I₂ = 2 A

Now, kirchoff's current law or junction law states that the total current flowing into the junction is equal to the total current flowing out of the junction.

We see that the third wire which is above the junction has it's current flowing out of the junction. Thus;

I₁ + I₂ = I₃

3 + 2 = I₃

I₃ = 5 A

Read more about kirchoff's current law at; brainly.com/question/86531