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?

No, the assumption is not reasonable.

Explanation:

The density of a white dwarf star is ; therefore, the mass of a basketball-sized fragment of white dwarf will be

where is the volume of the fragment.

For radius , the volume will be

Therefore, the mass of the fragment is  

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.

what was the acceleration of the 2 kg cart?

⇒ 16.0 cm/s2

what was the acceleration of the 4 kg cart?

⇒ 8.1 cm/s2

what was the acceleration of the 6 kg cart?

⇒ 5.3 cm/s2