(a) The electron kinetic energy is

which can be converted into Joule by keeping in mind that

So that we find

The kinetic energy of the electron is related to its momentum p by:

where m is the electron mass. Re-arranging the equation, we find

And now we can use De Broglie's relationship to find its wavelength:

where h is the Planck constant.
(b) By using the same procedure of part (a), we can convert the photon energy into Joules:

The energy of a photon is related to its frequency f by:

where h is the Planck constant. Re-arranging the equation, we find

And now we can use the relationship between frequency f, speed of light c and wavelength

of a photon, to find its wavelength:
The correct answer for the volume v of the solid obtained by rotating the region bounded by the given curves about the specified line. y = x2, y = 4x is 128/3 * π.
Volume of Solid of Revolution by Shell method is given by
V = 2π * integrate x(height) dx Here, height = 4x-x2
(1)& x-varies from x = 0 to x = 4 then from eqn(1) V = 2π * integrate x(4x - x ^ 2) dx from x = 0 to 4 = 2π * integrate (4x ^ 2 - x ^ 3) dx from x = 0 to 4
Basic Rule(1) ∫ x^n dx =x^ n+1/ n+1
V=2 π [4((x ^ 3)/3) - (x ^ 4)/4] 0 ^ 4 =2 π[ 4/3 x^ 3 - x^ 4/4 ] 0 ^ 4
V = 2π [4/3 * 4 ^ 3 - (4 ^ 4)/4} - 0]
V = 128/3 * π.
Learn more about area under curve here :-
brainly.com/question/15122151
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Explanation:
The emf is equal to the work done on the charge per unit charge (ϵ=dWdq) when there is no current flowing. Since the unit for work is the joule and the unit for charge is the coulomb, the unit for emf is the volt (1V=1J/C).
You might want to go to this website, http://www.indiana.edu/~p1013447/dictionary/mendel.htm
Welcome, And i hope this helps :P