Question

The amount of resistance, y, in a circuit varies inversely to the current, x, in the circuit. When 10 ohms of resistance are used in the circuit, 12 amperes of current are present. When 5 ohms of resistance are used in the same circuit, 24 amperes of current are present. How many ohms of resistance are used in the circuit when 15 amperes of current are present? Round your answer to the nearest hundredth, if necessary.

Answer 1

8 ohms

Explanation:

given that y varies inversely as x then the equation relating them is

y =
`\frac{k}x}` ← k is the constant of variation

To find k use either of the given conditions

y = 10 when x = 12 or y = 5 when x = 24, hence

k = 10 × 12 = 120

y =
`(120)/(x)` ← equation of variation

when x = 15, then

y =
`(120)/(15)` = 8