The amount of current flowing into an electrical circuit varies inversely as the resistance in the circuit. When the resistance of a particular circuit is 5 ohms, the current is 42 amperes. what is the current when the resistance is 4 ohms?

I = E/R

42 = E/5 so E = 210 volts

at R=5 ohms,

I = 210/4 = 52.5 amps

To find the current when the resistance is 4 ohms, you can use the concept of inverse variation.

The inverse variation equation can be represented as:

Current = k / Resistance

where "k" is the constant of variation.

Given that the current is 42 amperes when the resistance is 5 ohms, we can solve for "k" using this known data.

42 = k / 5

To isolate "k," multiply both sides of the equation by 5:

210 = k

Now that we know "k" is 210, we can use this value to find the current when the resistance is 4 ohms:

Current = k / Resistance
Current = 210 / 4
Current ≈ 52.5 amperes

Therefore, when the resistance is 4 ohms, the current flowing into the circuit is approximately 52.5 amperes.

To find the current when the resistance is 4 ohms, we can use the principle of inverse variation. Inverse variation is a mathematical relationship where the value of one variable decreases as the value of the other variable increases.

In this case, we know that the current (I) is inversely proportional to the resistance (R). Mathematically, this can be expressed as:

I ∝ 1/R

Where ∝ represents proportional to. Now, we can set up a proportion to solve for the current when the resistance is 4 ohms:

I1 / R1 = I2 / R2

Substituting the given values, we have:

42 A / 5 Ω = I2 / 4 Ω

To solve for I2, we can cross-multiply and then divide:

42 A * 4 Ω = 5 Ω * I2

168 AΩ = 5 Ω * I2

Dividing both sides by 5 Ω, we get:

I2 = 168 AΩ / 5 Ω

Simplifying the units:

I2 = 33.6 A

So, when the resistance is 4 ohms, the current flowing into the circuit is 33.6 amperes.