Imagine that you are trying to stop neutrinos with a lead shield. How thick would you need to make this shield to ensure that it can stop a neutrino?
A) About one meter.
B) About 700,000 kilometers (the radius of the Sun).
C) About 150 million kilometers (the size of an astronomical unit).
D) About one light year.
E) About 14 billion light years (the size of the observable universe).

Question

Quizplus · Accepted Answer

Neutrinos interact very weakly with matter, so an extremely thick shield, on the order of the size of the observable universe, would be needed to stop them.

Imagine That You Are Trying to Stop Neutrinos with a Lead