Calculations Made Easy for Beginners

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The discussion focuses on simplifying calculations for beginners, particularly in estimating surface area and energy. Participants emphasize the importance of unit conversion, noting that surface area should be calculated correctly to avoid errors. A specific example is provided, calculating the surface area of a person based on height and width, but highlights a mistake in converting from cm² to m². Additionally, the conversation reminds users to consider that only one side of a person is exposed to sunlight when performing energy calculations. Accurate unit handling and understanding the context of the calculations are crucial for beginners.
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How about you start with question a)
It's an estimate, so go look in a mirror... as long as you don't come up with 5 cm² or 12 m² or something in m³ or kW/m you're fine.

For b), I think the question is fairly straightforward. But if you have no idea, you can look at the units. You are given something in J/(s m²), something in m² (from a) and something in s (a duration is given in the question). The units you need to have are J (Joules, you are asked for an energy). How can you combine these?
 
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Acstars said:
For a if the average height was 170cm and the width is 30cm.
Surface area = height X width
SA = 170 X 30
SA = 5100cm
SA = 51m^2
It seems pretty off though?

5100cm² seems right, but there is an issue in your conversion to m².
 
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