sTRobeeRiii. . x))

im currently studying physics. i get a test on radioactivity for tomorrow test. so umm i'll just post it *some of my revision* i dunno why but it helps me to remember. hhee x)) dont read it if you dont like physics *read:FISIKA*

characteristic of radioactivity (1) random in space: which atom will decay first (2) random in time:when atom will decay.
decay happens to unstable nucleus. when the atom changes by emitting alpha, beta or gamma emmision.

alpha stated as helium atom 4n 2p *p=protons n=neutrons* it has the best ionisation and least penetration, it can stop by a paper
beta stated as an electron atom 0n -1p it has medium ionisation *has equal mass as electron* and medium penetration, it can be stop by 5mm aluminium
gamma is an excess energy it has neutral charge *zero charge* and it has the least ionisation *least mass of the three* but best at penetration as it is very light

Deflection in magnetic field. alpha will attracts to negative charge while beta will attract to positive charge. they both deflect perpendicular according to FLEMMING LEFT HANDLAW.
deflection can count by the Geiger Muller counter (GM counter). the radiation that comes to the counter will ionised the gas *argon* and a pulse of current will flows then the counter will count the current in count per secs unit.

then there's photographic films which can detect radiation and they;re using safety badges.

half life is the time taken for sample to decay to its half values and its constant.

safety (1) storage : put in a lead box, use hazard warning symbol (2) using and handling : use protective clothes, use lead shield, dont eat near the radiation, use tongs

alpha particle scattering proves : the nucleus is small, the nucleus is positive, the nucleus is heavy
isotopes is an atom with the same number of proton but different number of neutron, unstable isotopes is radioactive *sometimes*

uses of isotopes (1) treating cancer : focus the ray on the cancer from different sides to have less damage on healthy cell, use gamma rays which has best penetration and less ionising. it is uses short half life (2) finding out the leaks in a buried pipe : flows the radioactive material through the pipe, then it will leaks out to any leaks or hole that then can be detected by the counter.

huuff. . i need to pray *tarawehan* ahaiah x))
wishmeLuck yeshh ppL. ^^

|