When a potential difference of 10 V is placed across a certain solid cylindrical resistor,the current through it is 2.0 A.If the diameter of this resistor is now tripled,the current will be 18 A.

Question

Quizplus · Accepted Answer

Let's assume the initial diameter of the cylindrical resistor is d.

From Ohm's law, we know that the resistance of the resistor can be calculated as R = V/I, where V is the potential difference across the resistor and I is the current passing through it.

So, the initial resistance of the resistor is:

R1 = 10/2 = 5 ohms

Now, when the diameter of the resistor is tripled, its cross-sectional area becomes 9 times the initial area. Therefore, the resistance of the resistor will reduce to (1/9)th of its initial value. Let's assume the new resistance is R2.

R2 = R1/9 = 5/9 ohms

Next, we can use Ohm's law again to calculate the new current passing through the resistor when a potential difference of 10 V is applied across it:

I2 = V/R2 = 10/(5/9) = 18 A

Therefore, it is true that the current through the resistor will be 18 A when its diameter is tripled.

When a Potential Difference of 10 V Is Placed Across