Question

if humans cannot see ultraviolet waves, how can ultraviolet light be used to gather evidence of a crime? ultraviolet light detects the presence of radioactive substances. ultraviolet light shows cold areas as blue and warm areas as red. ultraviolet light causes substances to fluoresce and give off visible light. ultraviolet light transmits information to am and fm radio receivers.

Explanation:

Ultraviolet light can cause certain substances like bodily - fluids, dyes, and some minerals to fluoresce. Fluorescence is the process where a substance absorbs ultraviolet light and then emits visible light, which can be seen by humans. This property is used in crime - scene investigation to detect evidence that is otherwise invisible to the naked eye.

Answer:

Ultraviolet light causes substances to fluoresce and give off visible light.