Question

In the classic 1960s science fiction comic book The Atom, a physicist discovers a basketball-sized meteorite (about 10 cm in radius) that is actually a fragment of a white dwarf star. With some difficulty, he manages to carry the meteorite back to his laboratory. Estimate the mass of such a fragment. Is the assumption that he could carry it back reasonable?

Answer 1

Answer:

No, the assumption is not reasonable.

Explanation:

The density $\rho$ of a white dwarf star is $\rho = 1*10^9kg/m^3$; therefore, the mass $M$ of a basketball-sized fragment of white dwarf will be

$M =\rho V$

where $V= \dfrac{4}{3} \pi r^3$ is the volume of the fragment.

For radius $r = 0.1 m$, the volume will be

$V= \dfrac{4}{3} \pi (0.1)^3\\\\V = 4.12*10^{-3}\:m^3$

Therefore, the mass $M$ of the fragment is  

$M =\rho V= (1*10^9kg/m^3)* (4.12*10^{-3}\:m^3)$

$\boxed{M = 4.12*10^6kg}$

which greater than the weight of an average airplane. So could the physicist carry this weight back to his laboratory? Nope. This assumption that he could carry a weight larger than an airplane is unreasonable. No human or animal can lift this much.