Orbit about star, emission spectrum of light

AI Thread Summary
The discussion revolves around the application of the Bohr model to calculate the frequency of revolution of an electron and its relationship to the emission spectrum of light. Participants are tasked with demonstrating that, at large quantum numbers, the frequency of revolution aligns with the frequency of radiation emitted during electron transitions. Additionally, the problem involves calculating the mass of a black hole based on the emission spectrum of a proton orbiting it, with specific frequency adjustments. Users express difficulty in finding the necessary equations to solve for both the mass of the black hole and the radius of the proton's orbit. The conversation highlights the need for additional equations to progress in the calculations.
unscientific
Messages
1,728
Reaction score
13

Homework Statement



Show that in the Bohr model, the frequency of revolution of an electron in its nth

In classical physics, the frequency of revolution of the electron is equal to the
frequency of radiation it emits. Show that when n is very large, the frequency of
revolution is equal to the frequency radiated upon transition of the electron from orbit
(n+ 1) to n (Bohr’s correspondence principle). [5]
Assume that a proton is orbiting a black hole under the sole influence of gravity.
It produces an emission spectrum equivalent to that of a hydrogen atom, but with
frequencies multiplied by a factor of 10−6
. Disregarding relativistic effects, calculate
the mass of the black hole which would explain the observed emission spectrum. Show
that the radius of the proton’s orbit is proportional to the square of the quantum number
n and find the radius of the first orbit.

mj8okw.png


Homework Equations





The Attempt at a Solution



1 equation, 2 unknowns. Not sure how to calculate mass of star in the first place..

fxwyu.png
 
Physics news on Phys.org
anyone?
 
Have you found an expression for the frequency of revolution of the proton around the black hole?
 
milesyoung said:
Have you found an expression for the frequency of revolution of the proton around the black hole?

Yes, it is simply the above * 10-6. Problem is, to solve for M and r, I need at least 1 more equation
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top