Log in
Physics
1
answer
0
watching
116
views
23 Nov 2019

I need help understanding/explaining this question asked:

Question: Ifthe size of an atom is ~10-10 meters, the size of anucleus is ~10-15 meters, and knowing that the size ofan electron is less than 10-18meters (thus, atoms are almostempty), then why are atoms not transparents for visible light?

Need good explanation of answer. Thanks!

Watch
1
answer
0
watching
116
views

For unlimited access to Homework Help, a Homework+ subscription is required.

Deanna Hettinger
Deanna HettingerLv2
26 Sep 2019

Unlock all answers

Get 1 free homework help answer.
Already have an account? Log in
Share

Related textbook solutions

Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

Related questions

I am having trouble with distinguishing between when I need to use magnitude and when not to. This applies to more than just question 27, but I am using it as an example. In the first step why do you use the magnitude of the electron in proton (thus getting rid of the minus sign) where in other problems that are pretty similar, the minus sign is still there. Or do you always use the magnitude and the minus sign I am seeing is coming from somewhere else? Thanks.

One facet of the central field approximation for many-electronatoms is that inner-shell electrons screen the nuclear charge. Tounderstand how this works quantitatively, first note that theprobability distributions for electrons in different shellsgenerally do not overlap much. For instance, the electrons in the Mshell (n=3) are almost always farther from the nucleus than theelectrons of the K (n=1) and L (n=2) shells. Thus, it is a goodapproximation to assume that the inner shells completely screen thenucleus from the outer shells. For example, if there are tenelectrons altogether in the K and L shells of an atom, then theelectrons in the M shell experience force from a charge of roughlyZ-10, where Z is the charge on the nucleus as an integer multipleof e, the magnitude of the charge on an electron. This is calledthe effective nuclear charge Z_eff.

a. In a beryllium atom (Z=4), how many electrons are in the Kshell?
Express your answer as an integer.

b. n xenon (Z=54), what is the effective charge Z_eff experiencedby an electron in the M (n=3) shell?
Express your answer as an integer.

c. How many electrons are there altogether in the K, L, and Mshells of xenon? Recall that for n=3, the orbital quantum number lmust be zero, one, or two and that m_l can take any value betweenpostive and negative l.
Express your answer as an integer.

d.

The idea of simply subtracting the number of inner-shell electronsworks well only for atoms with low values of Z. For atoms withlarger nuclear charge, the different shapes of the probabilitydistributions for different subshells becomes an important factor.For instance, in the N shell, electrons in the s subshell have amuch higher probability than those in the p or d subshells of beingfound closer to the nucleus than some of the K, L, or M electrons.It is said that the s electrons penetrate the inner shells morereadily than do the p or d electrons. Therefore, it is to beexpected that our simple subtraction model may not work well forouter-shell s electrons in large atoms. Keeping this in mind, wesee that the effective nuclear charge Z_eff for the outermostelectron in an atom may be found experimentally by measuring theionization energy of an atom and then calculating the effectivecharge using the equation

E_n=- \frac{Z_{\rm eff}^2}{n^2}(13.6\;\rm eV).

The energy for the 5p valence electron in indium (Z=49) is -5.79electron volts. What is the effective nuclear charge Z_effexperienced by this electron?
Express your answer to three significant figures.

A lever enables you to lift objects that are too heavy to lift byhand. The lever pictured here consists of a long board placed on apivot. To lift the concrete slab on the left end of the board, theperson pushes downward on the right end.

A. Using the concept of torque, explain why a lever makes it easierto lift the heavy slab. Hint: in order for the board to "swing"clockwise, thereby lifting the slab, how must the torque exerted bythe person on the board compare to the torque exerted by the slabon the board?

B. The slab weighs 1000 Newtons. The segment of the board to theright of the pivot is 5 times longer than the segment of the boardto the left of the pivot. Assuming the board is very light, howhard must the person push down on the right end of the board tolift the slab?

C. A student last year gave this explanation for why this leverworks:
"if you take the slab off the board, and if the student lets go ofthe board,the board will naturally swing clockwise; it ends up withits right end on the ground. thats because the weight of the boardto the right of the pivot is greater than the weight of the boardto the left of the pivot. My point is, even with the slab in place,the weight of the board "helps" the student make the board swingclockwise. Thats why the students force on the board can be lessthan the slabs weight"

In what ways do you agree or disagree with this explanation? hint:itll help to check for coherence between your answer here and youranswers to A and B.


PLEASE PLEASE PPLEAASEE HELP ME ANSWER THIS!! I HAVE ABSOLUTELY NOCLUE ON HOW TO START. BUT PLEASE ,IF YOU ANSWER THIS, BE GOOD ATEXPLAINING THOROUGHLY, MY TA WILL SERIOUSLY TAKE POINTS OFF FOR THESLIGHTEST THING. SORRY FOR SUCH LONG QUESTION. :/ THANKS IN ADVANCE

Weekly leaderboard

Home
Homework Help 3,900,000
Physics 110,000
Start filling in the gaps now
Log in