[考古] 朋友的弟弟問的,請神人出手幫忙
如果不合板規請告知
我會馬上刪掉
同學弟弟問的
但是因為我年代久遠
所以心有餘而力不足
希望版上神人可以出手幫忙一下
萬分感恩
1.According to Quantum mechanics,draw the atomic structure of a neautral atom
with five electrons.
2.Which of the following statement is not true ?
(A) an electron's inherent magnetic moment is called the electron spin
(B) a piece of iron has strong magnetic effects because the atomic magnetic
moment aligned
(C) charged particles will spiral around the magnetic field if they have
velocity component parallel to the field direction
(D) the Hall voltage will decrease if the material stays longer in the
magnetic field
(E) a moving charged particle creats circular magnetic field around
it,perpendicular to its path
3.The radiation dose equivalent H (unit: Sv=J/kg ) is a measure of the risk
or biological effect associated with an exposure to ionizing radiation . It
is obtained by H=D×RBE ,where D is absorbed dose (unit: Gy=J/kg ) and RBE
(relative biological effectiveness ) is a dimensionless qualitiy factor of
radiation .The SI unit of H is sievert (西弗) or rem, 1Sv=1J/kg .
A 75kg worker at a breeder reactor plant accidentally ingests 5.0 mg of 239Pu
dust for one hour and receives a whole body radiation dose D of 0.04Gy by
alpha particles for which the RBE factor is 20. Calculate (a)the absorbed
energy in joules and (b) the dose equivalent H in sievert .
(Note that amount of radiation exposure expectedto cause significant halm to
humans is 3 Sv and highest report level during Fuku
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