# Elementary particle

1. Mar 14, 2008

### rojasharma

Elementary particle(ANYONE PLZ HELP ME WITH THIS Q)

The charge-to mass ratio of the pi^- particle was determined. The charge-to-mas ratio of the electron is 1.76x10^11C/kg. a) predict which particle has a greater mass-the electron, or the particle. b) use the value of the elmentary charge to calculate the mass of the pi^- particle in kg. Compare the mass of the particle to the mass of the electron.
for a) i think charge has greater mass... b) i think i have to use q/m=c/r...

Last edited: Mar 14, 2008
2. Mar 14, 2008

### tiny-tim

Hi rojasharma!

You started an identical thread yesterday:

(a) If no-one replies, you can always "bump" the thread up to the top of the list by adding a second post yourself - something like "Anybody? Please help!!"

A lot of people do that, and it saves duplication of threads.

(b) I didn't reply to the original thread because there wasn't enough information in it (I suspect the other 25 people who saw it felt the same).

In particular, I have no idea what the electron has to do with the π-.

Can you provide more detail?

3. Mar 14, 2008

### rojasharma

well...this is it.....this is what the exact question is in the book. What i was thinking was q/m is the ratio which is 1.76x10^C/kg, i can use this to find m by pluging into q/m=the ratio, therefore q/ratio = m......but i m confused...is this m what the part b wants???

4. Mar 14, 2008

### tiny-tim

Sorry, rojasharma, I still don't understand what the electron has to do with the π-.

is this question a sequel to some other question?

5. Mar 14, 2008

### rojasharma

The charge to-mass ratio of the pi^- particle was determined in the example above.The charge-to mass ratio of the pi^- particle was determined. The charge-to-mas ratio of the electron is 1.76x10^11C/kg. a) predict which particle has a greater mass-the electron, or the particle. b) use the value of the elmentary charge to calculate the mass of the pi^- particle in kg. Compare the mass of the particle to the mass of the electron.
this is the exact question.....and above this question there is no example given however.....in the lesson there is an example that gives the charge-to mass ratio of the pi^- particle...i am not sure if i am supposed to use that value? should i post the charge-to mass ratio for pi^- from the example in the lesson?

6. Mar 14, 2008

### tiny-tim

Yes, I think that must be what is intended.

(btw, if you type alt-p and -, it prints π- for you!)

7. Mar 14, 2008

### rojasharma

the charge-to-mass ratio for alt-p- is 8.6x10*C/kg

8. Mar 14, 2008

### rojasharma

so for b....q/m=ratio of pi-, do i sud in 1.6x10^-19 for q??...so 1.6x10^-19/8.6x10^8C/kg which gives me m=1.86x10^-28kg......doesn;t seem right to me:(.....HELP!!!!!

9. Mar 14, 2008

### rojasharma

10. Mar 17, 2008

### tiny-tim

… looks ok to me …

Hi rojasharma!

Let's see …

charge = charge/mass x mass;

so mass = charge/(charge/mass)

= 1.6x10^-19 / 8.6x10^8C/kg

= 1.86x10^-28kg.

Looks ok to me - the mass of the pion is about 10^-28kg.