Question

A radiation dosage of 500 REM is already lethal, a person may have a 50% chance of surviving this dose.

True

False

The nucleus consists of several nucleons (basically protons and neutrons) tied together by very strong forces.

True

False

Radioactivity is related to drastic changes that occur in:

		outer regions of atoms
		the atomic nucleus
		atomic electrons
		None of the above

Radioactivity was first discovered in Uranium, but later other substances as Thorium, Actinium, and Radium were found. These materials were thoroughly studied by:

		Wilhelm Roentgen
		Marie and Pierre Curie
		Henri Becquerel
		None of the above

Answer 1

Three are three types of radiations, Alpha, Beta, and Gamma radiation. In which Gamma can penetrate more than remainig two. The amount od radiation dose described by 'rem'. If the does 100 rem received in a short time can cause observable health effects and received for longer time will effect the health.

Therefore, 500 rem recieved in short time can have 50% chance of surviving.

Hence, it is true.

(2) True. The nucleons are held together by strong forces and short range forces called nuclear forces, regardless of the charge of the nucleons.

(3) The heavy nuclei, which are unstable are constantly changing as a result of the imbalance of energy within the nucleus. The radioactivity related to atomic nucleus.

(4) Radioacitivity discovered by Henri Becquerel, in his observations uranium emittes radiation.

The term radioactivity was actually coined by Marie Curie,along with Pierre, began investigating the phenomenon discovered by Becquerel. They concluded that the ore contained other radioactive elements. This led to the discoveries of the elements polonium and radium.