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An 850 W consumer coffee maker can make ...

An 850 W consumer coffee maker can make 10 cups (1.75 litres) of `80^(@)C` coffee from `20^(@)C` tap water in 10 minutes. What percentage of the electrical energy consumed actually makes it to the coffee?

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To solve the problem, we need to calculate the percentage of electrical energy consumed by the coffee maker that actually goes into heating the coffee. We will follow these steps: ### Step 1: Calculate the heat required to raise the temperature of water We use the formula for heat energy required: \[ Q = mc\Delta T \] ...
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