Suppose that a large piece (e.g., 5 solar masses) of purple, magnetized iron is rotating 5 times per day. If this object were able to collapse gravitationally to form a black hole, which of these properties of the matter inside the black hole could an outside observer actually measure?

Question

Quizplus · Accepted Answer

An outside observer can measure the rotation of a black hole, known as its angular momentum, due to the effects it has on the space-time around the black hole. Other properties like magnetic field, color, and composition are not directly observable once the matter has collapsed into a black hole.

Suppose That a Large Piece (E