Question

The current I in an electrical conductor varies inversely as the resistance R of the conductor. The current is 1/2 ampere when the resistance is 400 ohms. What is the current when the resistance is 2500 ​ohms?

Answer 1

The current is 0.08 ampere.

Explanation:

Given:

The current is 1/2 ampere when the resistance is 400 ohms.

Now, the current I in an electrical conductor varies inversely as the resistance R of the conductor.

So, as per formula
`I = (k)/(R)`

Solving for "k" using the current 1/2 amperes when the resistance is 400 ohms.

`(1)/(2) = (k)/(400)`

By cross multiplication we get:

`2k=400\\k=(400)/(2)=200`

Putting the value of
`k` for solving the equation:

`I =\frac {200}{R}`

Now, the current when the resistance is 2500 ohms:

`I = (200)/(2500)`

`I = 0.08`

`I = 0.08` ampere.

Therefore, the current is 0.08 ampere.