- #1

songoku

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- Homework Statement
- a. If a positron beam were to be used as an annihilation cutting tool, calculate the beam current that would deliver 100 kW.

b. What voltage would be needed to accelerate beam of electrons so that, at the same beam current, it could deliver the same power from mechanical collisions with the target?

- Relevant Equations
- ##E=mc^2##

##E=hf##

##\lambda = \frac h p##

##\frac{1}{2} mv^2 = q.V##

P = V.I

a) My idea is:

1. Find the energy created by annihilation process, which is ##E=2mc^2## where m is the mass of electron

2. Find the wavelength of photon by using formula E = hf

3. Find the speed of positron by using the formula of de broglie wavelength

4. Find the p.d by using conservation of energy: ##\frac{1}{2} mv^2 = q.V##

5. Find current by using P = V.I

I am not sure at step (3) because I use the wavelength of photon as wavelength of positron. Can I do this?

b) I just use P = V.I to find V, which is the same as what I found in part (a) step (4)

Am I correct? Thanks

1. Find the energy created by annihilation process, which is ##E=2mc^2## where m is the mass of electron

2. Find the wavelength of photon by using formula E = hf

3. Find the speed of positron by using the formula of de broglie wavelength

4. Find the p.d by using conservation of energy: ##\frac{1}{2} mv^2 = q.V##

5. Find current by using P = V.I

I am not sure at step (3) because I use the wavelength of photon as wavelength of positron. Can I do this?

b) I just use P = V.I to find V, which is the same as what I found in part (a) step (4)

Am I correct? Thanks