Manipal Entrance Test 2015 Physics Paper

The damage caused by the γ-radiation is less serious as compared to damage caused by the a-radiation. This is because α-radiation is more dangerous than beta or gamma if ingested because its power to ionize or to disrupt, atoms is 20 times more than β and γ. But if the source is outside the body or at a distance gamma radiation is much dangerous because it could penertrate thick walls of skin.