Why did Rutherford carry out his experiments in the dark?

Ernest Rutherford conducted his experiments in the dark to minimize the interference of external light on his observations, particularly when he was studying the behavior of alpha particles emitted from radioactive materials. This allowed for more accurate detection of the particles as they interacted with the gold foil and the surrounding detectors. The darkness helped ensure that the experiments were sensitive enough to reveal subtle interactions, which were crucial for understanding atomic structure.