Is it possible to calculate the rest mass of a pion given only its E ?

rwooduk
Messages
757
Reaction score
59
The TOTAL energy of a pion is given, no other information is given so we don't know how fast it is moving, is it possible to calculate its mass? I'm assuming it's relativistic and we need GAMMA (the lorentz factor)

Also if E is it's total energy what would it's kinetic energy be? wouldn't its kinetic energy be its total energy?


Thanks in advance for any help on this, I've been going round and round in circles.
 
Physics news on Phys.org
E = mc2 should help you find the mass when E is given :smile:
Here m is not the rest mass, because that requires ##\gamma## for ##m = \gamma m_0##.
So if are they asking for the rest mass the answer is no.
But you ask whether it's possible to calculate the mass (period).
 
  • Like
Likes 1 person
Thanks very much for the reply!

Very helpful.
 
Thread 'Need help understanding this figure on energy levels'
This figure is from "Introduction to Quantum Mechanics" by Griffiths (3rd edition). It is available to download. It is from page 142. I am hoping the usual people on this site will give me a hand understanding what is going on in the figure. After the equation (4.50) it says "It is customary to introduce the principal quantum number, ##n##, which simply orders the allowed energies, starting with 1 for the ground state. (see the figure)" I still don't understand the figure :( Here is...
Thread 'Understanding how to "tack on" the time wiggle factor'
The last problem I posted on QM made it into advanced homework help, that is why I am putting it here. I am sorry for any hassle imposed on the moderators by myself. Part (a) is quite easy. We get $$\sigma_1 = 2\lambda, \mathbf{v}_1 = \begin{pmatrix} 0 \\ 0 \\ 1 \end{pmatrix} \sigma_2 = \lambda, \mathbf{v}_2 = \begin{pmatrix} 1/\sqrt{2} \\ 1/\sqrt{2} \\ 0 \end{pmatrix} \sigma_3 = -\lambda, \mathbf{v}_3 = \begin{pmatrix} 1/\sqrt{2} \\ -1/\sqrt{2} \\ 0 \end{pmatrix} $$ There are two ways...
Back
Top