1. What is the closest estimate of the volume of an adult human in cubic meters?
a. 2.5
b. 1.25
c. 0.1
d. 0.75
Closest Estimate of the Volume of an Adult Human
The closest estimate of the volume of an adult human in cubic meters is 0.1 m³.
The human body’s volume can be derived from its average mass divided by its density. As human density is approximately equal to that of water (1000 kg/m³), and the average adult mass ranges between 62–80 kg, this gives a volume between 0.062–0.080 m³. For simplicity, physics problems often round this value to 0.1 m³.
Experimental measurements confirm volumes around 62–65 liters (0.062–0.065 m³), making 0.1 m³ the closest estimate among typical multiple-choice options.
Option Analysis
- a. 2.5: Far too large; equals 2500 liters or a small room, over 30 times the actual size.
- b. 1.25: Still excessive at 1250 liters; comparable to a large hot tub, around 15× too high.
- c. 0.1: Accurate approximation. For a 70 kg person: 70 kg / 1000 kg/m³ = 0.07 m³. Physics estimates often use 0.1 m³ directly.
- d. 0.75: High at 750 liters; roughly equivalent to a large bathtub, about 10× too much.
Calculation Breakdown
Volume is given by the formula:
V = m / ρ
Where:
- m ≈ 70 kg
- ρ ≈ 1000 kg/m³
Substituting these values gives:
V = 70 / 1000 = 0.07 m³
A simple dimensional estimate (1.7 m height × 0.5 m width × 0.1 m depth) yields approximately 0.085 m³, which supports 0.1 m³ as the best approximate volume for an adult human.
