physics test 2 Flashcards
what is fusion
reaction where 2 or more nuclei combine to form one or more different atomic nuclei
what is fission
when a neutron slams into a larger atom forcing it to split into two different atoms
why are gamma rays used in medicine
they are used for radio therapy to kill cancer cells through aiming gamma rays at the cells from different directions. they also have very little absorption so arent extremely harmful to innocent cells.
what is half life
the time it takes for half of the nuclei to decay or for the count rate to half
how do you find half life
read from a graph
why do electrons move closer or further away from the nucleus
energy is lost or gain
what charge does a protom have
+1
what charge does an electron have
-1
what charge does a nucleus have
0
what is an isotope
the same number of protons, but a different number of neautrons
what were the results of the alpha experiment
most alpha particles passed straight through, some alpha particles are deflected at diffetrent angles, some are bounced back from the gold
what was the conclkusion of the alpha experiment
positivley charged alpha particles were being repelled and deflected by a tiny concentration of positive charge in the atom, mass of the atom is concnetrated at the nucleus, nucleus is positivley charged
what is a alpha
2 protons and 2 neutrons
what is a beta
negativley charged electron, particle
what is a gamma
wave of pure energy and electromagnetic
