Please help! Any information to help me with the following question would be gre
ID: 1432818 • Letter: P
Question
Please help! Any information to help me with the following question would be greatly appreciated!
In this problem, we will investigate the design of a mass spectrometer, used to measure the mass of particles. A source S emits particles of mass m and charge q through a slit S_1. The particles pass through a region of crossed electric field E and magnetic field 3. In the diagram shown here, notice that the electric field points up and the magnetic field points out of the board. Only particles with the correct speed be unelected and pass through the suit at the end, S_2. Find the speed of the particles that pass through the slit. After emerging from S_2, the particles enter a region of uniform magnetic field B' and follow a circular path. Show that the position d where the particle lands on the detector is a function of the fields used in the device, known to the experiment, and the ratio m/q of the particle.Explanation / Answer
A) since electric field and magnrtic field are perpendicular to each other
they will exery equal and opposite forces on particles so that they pass undefelctedly and through thes lit s2
the condition for undefelcting is
Elecric force on particle = magnetic force on the particle
Fe = FB
q*E = q*v*B....
speed of the particles is v = E/B..
b) since the particle after passing through slit s2 it was moving in a circular path du to action of magnetc force on that
centripetal force = magnetic force on that particle
m*v^/r = q*v*B....
here r is radius of that orbit r = d/2...
m*v^2/(d/2) = q*v*B...
d/2 = m*v^2/(q*v*B) =m*v/(q*B)...
d = 2*m*v/(q*B)....(1)
from the above equation
we can show that d is a function of magnetic field and ration of m/q of the particle