Physics (AS & A Level) · May / June 2016 · Paper 21 · Question 1

(50 to 200) × 10–3 kg or (0.05 to 0.2) kg [1]

(50 to 300) cm3 [1]

density = mass / volume or ρ = M / V V = [π(0.38 × 10–3) 2 × 25.0 × 10–2] / 4 (= 2.835 × 10–8 m3) ρ = (0.225 × 10–3) / 2.835 × 10–8 = 7940 (kg m–3) ∆ρ / ρ = 2(0.01/0.38) + (0.1/25.0) + (0.001/0.225) [= 0.061] or %ρ = 5.3% + 0.40% + 0.44% (= 6.1%) ∆ρ = 0.061 × 7940 = 480 (kg m–3) density = (7.9 ± 0.5) × 103 kg m–3 or (7900 ± 500) kg m–3 [5]