Someone said, “Current takes the path of least resistance.” What’s wrong with this statement?

Short Answer

Expert verified

For the current to flow between the two points, there must be a potential difference; the value of resistances can be anything.

Step by step solution

01

Write the given data from the question.

The current takes the path of the least resistance.

02

Determine the formulas to find out the what’s wrong with the given statement.

The current is defined as the ratio of the voltage across the resistance and the resistance.

The expression to calculate the current through the resistance is given as follows.

I=VR …… (i)

Here, is the voltage across the resistance and is the resistance.

03

What’s wrong with the given statement.

From equation (i), it is clear that the current is inversely proportional to the resistance, which means the current flows more in the lower resistance.

If two resistances are connected in the series, the current will be the same in both resistances, and the values of the resistance can be anything. But when the two resistances are connected in parallel, the current will not flow only through the resistance with a low value. The current will flow in both the resistance but in the inverse proportion of their resistance.

In some cases, when one resistance is vast compared to the other, some current will flow through the lower resistance, but we take it as zero to make the calculation easier.

For the current to flow between the two points, there must be a potential difference; the value of resistances can be anything.

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