DENSITY AND PRESSURE

2 marks · Easy

A block of plastic has a mass of 800 g and a volume of 0.002 m³. Calculate the density of the plastic in kg/m³. Give your answer to 2 significant figures.

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400 kg/m³ (±2)

Also accept: Accept 400 with or without unit; 400.0

Common mistakes: Forgetting to convert g to kg

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Marking points

M1 · 1 mark · Converts mass from g to kg, substitutes values into density formula

A1 · 1 mark · Final answer correct with unit and 2 significant figures

Worked solution

First, convert mass to kg: 800 g = 0.8 kg.

Substitute: p = 0.8 / 0.002 = 400 kg/m³.