In the early years of the 20th century, a leading model of the structure of the
ID: 1535879 • Letter: I
Question
In the early years of the 20th century, a leading model of the structure of the atom was that of the English physicist J. J. Thomson (the discoverer of the electron). In Thomson's model, an atom consisted of a sphere of positively charged material in which were embedded negatively charged electrons, like chocolate chips in a ball of cookie dough. Consider such an atom consisting of one electron with mass m and charge e, which may be regarded as a point charge, and a uniformly charged sphere of charge +e and radius R.
Calculate the frequency of oscillation.
Express your answer in terms of the variables m, R, e, and constants and 0.
Explanation / Answer
Electric field inside the sphere is,
E = k*Q*r / R^3
E = Ke*r / R^3
for dispalcement r ,
Force is,
F = K*e^2* r / R^3
centrepetal force is,
F = m*w^2*r
w = sqrt(K*e^2 / m*R^3)
K = 1 / 4*pi*e0
frequecny f = w / 2*pi
f = sqrt (e^2 / 4*pi*e0*R^3*m) / 2*pi
answer