# Mass Spectrometer (B-field)

1. Oct 21, 2007

### wiz0r

1. The problem statement, all variables and given/known data

The problem can be found here;

http://www.physics.uprm.edu/~mark/courses/FISI3172_I2007/PracticeExamIII.pdf [Broken]

2. Relevant equations

Ok, ok. I made some reaserch, and I found that the;

radius of an ion orbit on a mass spectrometer = mv / qB

where m = mass, v = velocity, q = charge, B = magnetic field.

ok, now, if that holds true then;

m = rqB / v

3. The attempt at a solution

so, the answers are the following;

a) still don't know how the answer.

b) increases

c) increases

d) decreases

e) remain the same, since Temperature is not part of the equation, T will be a constant, and therefore the mass of the ions would stay the same?

Can anyone verify this? And help me with the answer to A?

Last edited by a moderator: May 3, 2017
2. Oct 21, 2007

### wiz0r

Ok, ok. I made some reaserch, and I found that the;

radius of an ion orbit on a mass spectrometer = mv / qB

where m = mass, v = velocity, q = charge, B = magnetic field.

ok, now, if that holds true then;

m = rqB / v

so, the answers are the following;

a) still don't know how the answer.

b) increases

c) increases

d) decreases

e) remain the same, since Temperature is not part of the equation, T will be a constant, and therefore the mass of the ions would stay the same?

Can anyone verify this? And help me with the answer to A?

3. Oct 21, 2007

### wiz0r

anyone?

4. Oct 21, 2007

### wiz0r

up..

5. Oct 21, 2007

### wiz0r

well, last try before i give up.

6. Oct 21, 2007

### hage567

For the first part, think about F = qv x B. How do you think you can determine the charge given this equation?