In a mass spectrometer a particle of mass m and charge q is ...

[Kikoku]

In a mass spectrometer a particle of mass m and charge q is accelerated through a potential difference V and allowed to enter a magnetic field B, where it is deflected in a semi-circular path of radius R.
 
  The magnetic field is uniform and oriented perpendicular to the velocity of the particle. Derive an expression for the mass of the particle in terms of B, q, V, and R. A)
 
  qB2R2/V
  B)
 
  qB2R2/(2V)
  C)
 
  q2B2R2/V
  D)
 
  q2B2R2/(2V)
  E)
 
  qB2R2/(V2)

Question 2

A metal blade of length L = 60 cm spins at a constant rate of 15 rad/s about an axis that is perpendicular to the blade and through its center.
 
  A uniform magnetic field B = 4 mT is perpendicular to the plane of rotation. What is the magnitude of the potential difference between the center of the blade and either of its ends?
  A)
 
  2.7 mV
  B)
 
  1.3 mV
  C)
 
  5.1 mV
  D)
 
  9.1 mV
  E)
 
  7.8 mV

[mfedorka]

Answer to Question 1

B

Answer to Question 2

A