One can not align the apparatus to eliminate entirely the effects of the Earth\'
ID: 2280782 • Letter: O
Question
One can not align the apparatus to eliminate entirely the effects of the Earth's magnetic field. Consider the case where electrons having accelerated through V then enter the uniform field region between the Helmholtz coils. With the coil current set to zero, the electron beam was observed to have a slight curvature due to the earth's magnetic field. The current in the coil had to be set to 0.522 A to set the electron beam exactly straight. If each coil has 61 turns and has a mean radius of 66.6 cm, calculate the component of the earth magnetic field perpendicular to the entering electron beam:
*answer in mT
Explanation / Answer
For the midpoint of Helmholtz Coils, Magnetic Field = [8/(5^3/2)] * [ mu * n * I / R]
= [8/(5^3/2)] * [ 4 * pi * (10^-7) * 61 * .522 / .666] = 4.3 * (10^-5) T = 4.3 * (10^-2) mT = 0.043mT
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.