An electric kettle has a resistance of 50 Ω. What current will flow when it is connected to a 220 V supply? Also find the power rating of the kettle.

Solution: To find the current flowing through the electric kettle and its power rating, we can use Ohm's law and the formulas for power in terms of voltage, current, and resistance.

Given:

• Resistance ($𝑅$) of the kettle = 50 Ω
• Voltage ($𝑉$) of the supply = 220 V

(a) Current flowing through the kettle:

We can use Ohm's law to find the current ($𝐼$) flowing through the kettle, which states:

$𝑉=𝐼𝑅$

Where:

• $𝑉$ is the voltage (220 V),
• $𝑅$ is the resistance (50 Ω),
• $𝐼$ is the current.

Rearranging the formula to solve for $𝐼$:

$𝐼=\frac{𝑉}{𝑅}$

Plugging in the given values:

$𝐼=\frac{220\text{V}}{50\mathrm{\Omega }}$

$𝐼=4.4\text{A}$

So, the current flowing through the electric kettle is $4.4\text{A}$.

(b) Power rating of the kettle:

We can use the formula for power ($𝑃$) in terms of voltage ($𝑉$) and resistance ($𝑅$), which is:

$𝑃=\frac{{𝑉}^2}{𝑅}$

Plugging in the given values:

$𝑃=\frac{(220\text{V}{)}^2}{50\mathrm{\Omega }}$

$𝑃=\frac{48400{\text{V}}^2}{50\mathrm{\Omega }}$

$𝑃=968\text{W}$

So, the power rating of the electric kettle is $968\text{W}$.