This question is about using the mains electricity supply - Edexcel - GCSE Physics - Question 5 - 2021 - Paper 1

We use the equation for energy transferred:

$E = I \times V \times t$

Where:

• $I = 7.4 \text{ A}$ (current in the coffee machine)
• $V = 230 \text{ V}$ (mains supply voltage)
• $t = 120 \text{ s}$

Substituting these values:

$E = 7.4 \text{ A} \times 230 \text{ V} \times 120 \text{ s}$

Calculating this yields:

$E \approx 204,240 \text{ J}$

So, the energy transferred to the coffee machine is approximately 200,000 J.

Wire X = neutral

Wire Y = live

Component Z = fuse

We use the equation:

$\text{input current} \times 230 \text{ V} = 2.37 \text{ A} \times 190 \text{ V}$

Rearranging gives us:

$\text{input current} = \frac{2.37 \times 190}{230}$

Calculating this yields:

$\text{input current} \approx 1.9 \text{ A}$

Thus, the input current to the transformer is approximately 1.9 A.