An archeologist finds a huge monolith in the desert. In order to estimate the weight of this object; he estimates the dimensions of the monolith and removes some chips from the rock with his hammer, collecting the following data:
Dimensions of the monolith = 1.5 m * 5.2 m * 13 m
Mass of rock chips = 41.73 g
Volume of rock chips = 15.2 cm³
Determine the mass of the monolith in pounds, assuming it is of uniform composition. (1 lb = 453.6 g)

Question

Quizplus · Accepted Answer

The volume of the monolith can be calculated by multiplying its dimensions:

Volume = 1.5 m x 5.2 m x 13 m = 101.4 m^3

The density of the rock can be calculated using the mass and volume of the rock chips:

Density = mass/volume = 41.73 g / 0.0152 m^3 = 2747.04 kg/m^3

Assuming the monolith has the same density as the rock chips, its mass can be calculated using its volume:

Mass = density x volume = 2747.04 kg/m^3 x 101.4 m^3 = 278787.22 kg

Converting to pounds:

Mass = 278787.22 kg x (1 lb / 453.6 g) = 6.11 x 10^10 lb

Rounding to one significant figure, the answer is 6.1 x 10^10 lb, which corresponds to choice (B).

An Archeologist Finds a Huge Monolith in the Desert