A pumpkin weighs 7.5 N. On submerging it completely in water, ¾ L of water gets displaced. The acceleration due to gravity at the place where the pumpkin was weighed is 10 m/s². Which one of the following is the correct value of the density of the pumpkin ?
10 kg/m³
100 kg/m³
1000 kg/m³
10000 kg/m³
Answer is Right!
Answer is Wrong!
This question was previously asked in
UPSC NDA-2 – 2024
Volume of water displaced (V_displaced) = 3/4 L = 0.75 L.
Converting litres to cubic meters: 1 L = 0.001 m³. So, V_displaced = 0.75 × 0.001 m³ = 0.00075 m³.
When completely submerged, Volume of pumpkin (V_pumpkin) = V_displaced = 0.00075 m³.
Density of pumpkin (ρ) = Mass / Volume = 0.75 kg / 0.00075 m³.
ρ = 0.75 / (7.5 × 10⁻⁴) = (7.5 × 10⁻¹) / (7.5 × 10⁻⁴) = 10³ kg/m³ = 1000 kg/m³.