The formula is 1/lamba = R (1/2^2 - 1/n^2)
sorry if that doesnt make sense
But i will put in the number 2 in n for one wavelength and infinity for the other wavelength - and then subtract the 2 answers to get the wavelength range?
Is this along the right lines?
In the textbook in a previous example - it says that the C-14 activity in a living tree is 255 Bq - that is where i got that value from but i wasnt sure if i could use that value in this question - ie is it always 255 Bq in living trees?!?
The half-life is in s^-1 - therefore the answer...
Yeh but what i dont understand is how many different energy levels there are for each of the series? Like does it go on forever or does it stop at a certain number? Ie they start at n = 2 or n = 3, but where do they stop? Do they go up to infinity? Is it as simple as plugging the number in for...
Q: What are the widths of the wavelength intervals over which (a) the Lyman series and (b) the Balmer series extend? (Each width begins at the longest wavelength and ends at the series limit.) (c) What are the widths of the corresponding frequency intervals? Express the frequency intervals in...
Q: A 50-g chunk of charcoal is found in the buried remains of an ancient city destroyed by invaders. The carbon-14 activity of the sample is 200 decays/min. Roughly when was the city destroyed?
A: I used R = Ro*e^(-lambda*t) and t1/2 = ln2/lambda
t1/2 = 3.834*10^-12 s-1
and 200...
Q: What is the minimum amount of energy necessary to remove a proton from the nucleus of a 42-Ca atom, thereby converting it into a 41-K atom? The former has a mass of 41.958618 u, the latter 40.961825 u, and the hydrogen atom has a mass of 1.007825 u.
My answer:
42-Ca --> 41-K + 1-H...
Can some please review this question and tell me if the working looks correct? Please advise of any mistakes i may have made. Thanks
Q: UV radiation (wavelength = 250 nm) falls on a metal target, and electrons are liberated. If the maximum kinetic energy of these electrons is 1.00*10^-19 J...
Q: Approximate the minimum kinetic energy of an electron confined to a region the size of an atom (0.10 nm)
How would one go about solving this? What equations/principles are involved and how do we use them?
Seems like a simple question but i have no idea where to start? :confused...
What happens in each of the situations though? i.e in parts a) b) and c) - what is different in each of them? And how do you explain these observations in terms of Gauss' Law and Flux?
Thanks :smile:
The membrane of a cell is electrically equivalent to a parallel plate capacitor. A typical cell has a spherical shape with a radius 10 μm and it has a potential of −60 mV with respect to outside. The thickness of the membrane is about 0.01 μm, and it has a dielectric constant of 2.
Find:
(a)...
I have no idea what principles i am supposed to use in this question? Could someone show me how to do this question please? Thanks :smile:
Calculate the electrical potential energy of two protons separated by 1 nm, and compare it with their gravitational potential energy. Estimate how heavy...
I dont really understand Gauss' law - any help with this question would be appreciated?
Coaxial cables are made of a copper wire in the center and a concentric cylindrical shell of copper outside, with insulating material in between and outside the shell. The charge per unit length of the...
Hi, i dont know how to do this question - some help would be appreciated.
Q: A patient is to be given a blood transfusion. The blood is to flow through a tube from a raised flexible bag to a needle inserted in the vein. The inside diameter of the 40mm-long needle is 0.40mm and the required...
So i let R = 0.8 on one side, and the final pressure as what im trying to find, and then on the other side i let R=1 as thats at the initial radius, and let the pressure equal 1 here asell and then solve for Final Pressure?
Thanks!
I need some help with this question.
Q: Poiseuille's equation shows that for laminar flow the volume flow rate through a pipe in proportional to the product of the pressure difference and the fourth power of the radius. The viscosity of water is 1.0*10^-3 Pa.s
a) Water in a pipe is flowing...
Some help with this question please?
a) An ice cube floats in a glass of water. When the ice melts, will the water level in the glass rise, fall, or remain unchanged? Justify your answer.
b) If the ice had been made from pure water, and the water in the glass was salt water (denser than...
Using the answer from the quadratic is obviously not the amplitude - it was incorrect. So where do i go from here? What does the speed of the plate have to do with the amplitude?
The total mechanical energy of the scale at the point of maximum displacement is given by 1/2*k*A^2 , where k is the...
So is this positive x value now the displacement after the ham hits the plate? Is it also the amplitude or is this just the new equilibrium position from where the plate and ham are at rest?
So then U = mg(h+x)
therefore: 0.3*9.8*(0.25+x) = 1/2*200*x^2
So then do you solve for x, using the quadratic formula?
I get x = 0.455 or x = -0.16
Which one would then be the displacement?
I got these answers from: 100x^2 - 29.4x -7.35
Am i doing the right thing now?
But then if mgh = 1/2kA^2
that means for the ham:
0.3*9.8*0.25 = 1/2*200*A^2?
I dont understand? Ive done that before but it doesnt work?
But what you are saying is to work out how far the ham goes past the 0.25m? I still dont understand how to get that?