•    Sometimes when we are hurt, doctors take an 'X-ray' photograph of the injured part to find out if there is any fracture in the bones.

•    X-rays were discovered by German physicist Wilhelm Conrad Roentgen in 1895.

X-ray of hand            X-ray of chest

•    Roentgen discovered these rays accidentally, while working in his laboratory.

•    In various experiments, he found that these rays were able to pass through tissues, but not bones.

•    Today, X-rays are commonly used in medicine (to diagnose fractures) and scientific research.