A spherical water droplet has radius 0.5 mm. Calculate the surface area of the droplet in mm².

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Question

A spherical water droplet has radius 0.5 mm. Calculate the surface area of the droplet in mm².

Accepted Answer

π mm² — Award 1 mark for correct substitution: Surface area = 4πr² = 4π(0.5)² = 4π(0.25) = π mm². B is incorrect — this evaluates π ≈ 3.14 rather than leaving in terms of π. C is incorrect — this omits squaring the radius. D is incorrect — this evaluates 4π instead of π.

Answer

12.6 mm²

Answer

3.14 mm²

Answer

π mm²

Answer

4π mm²

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