Radiations are used for the treatment of skin of a patient is_______________? A. Alpha raysB. Gamma rays C. Beta rays D. X-rays

The maximum safe limit dose for persons working in a nuclear power station is ________________? A. 1 rem per weekB. 5 rem per week C. 4 rem per week D. 3 rem per week

Which of the following will be a better shield against gamma rays ? A. Ordinary water B. Heavy waterC. Lead D. Aluminum

A device for producing high-velocity nuclei is ________________? A. Cloud chamberB. Linear accelerator C. A mass spectrograph D. Wilson cloud chamber

Pair production can take place only with_________________? A. X-raysB. Gamma rays C. UV-rays D. IR-rays

Pair production cannot take place in a vacuum as ________________? A. Mass is not conserved B. Energy is not conservedC. Momentum is not conserved D. The chargee is not conserved

Alpha particles possess greater penetration power than that of beta particles due to its_____________? A. Smaller ionization power B. Greater ionization power C. Neither greater nor smaller ionization power D. Same ionization power

Beta particles ionize an atom_________________? A. Due to the electrostatic force of attractionB. Due to the electrostatic force of repulsion C. Due to a direct collision D. Due to the gravitational force

Why gamma rays are used to kill bacteria to sterilize surgical equipment etc ? A. Chargeless B. MasslessC. Highly penetrating D. All of above