NDA 2 2024 GAT, question 92

Topic: Physics

Q92

A pumpkin weighs $7.5\text{ N}$ . On submerging it completely in water, $\frac{3}{4}\text{ L}$ of water gets displaced. The acceleration due to gravity at the place where the pumpkin was weighed is $10\text{ m/s}^{2}$ . Which one of the following is the correct value of the density of the pumpkin ?

(a) $10\text{ kg/m}^{3}$
(b) $100\text{ kg/m}^{3}$
(c) $1000\text{ kg/m}^{3}$ Correct answer
(d) $10000\text{ kg/m}^{3}$

Solution.

Answer: (c) $1000\text{ kg/m}^{3}$

Mass=weight/g=7.5/10=0.75 kg.
The displaced volume is the pumpkin volume, ¾ L=0.00075 m³.
Density=m/V=0.75/0.00075=1000 kg m⁻³.