Question

A photon scatters from a proton, initially at rest. After the collision, the proton is found to scatter at an

angle of 30 with the original direction of the incident photon with a kinetic energy of 100 MeV. Find (i)

the initial energy of the photon and (ii) the angle through it is scattered

Hints : The rest mass of proton is 938 MeV. Total energy of a relativistic particle is .

Use these to determine momentum of the scattered proton. Use momentum and energy conservation.

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Answer 1

Answer:

photon scatters from a proton, initially at rest. After the collision, the proton is found to scatter at an

angle of 30 with the original direction of the incident photon with a kinetic energy of 100 MeV. Find (i)

the initial energy of the photon and (ii) the angle through it is scattered

Hints : The rest mass of proton is 938 MeV. Total energy of a relativistic particle is .

Use these to determine momentum of the scattered proton. Use momentum and energy conservation.

Answer 2

Answer:

find relativistic momentum

(1038)^2-938^2= (pc)^2

equate momentum and eliminate angle between

photon . input pc =√197600

solve and get expression between E and E'

also

loss of energy of photon = total Kinetic energy of proton

E-E'=100Mev

this should give E'=229Mev and E=329Mev

by momentum equation in y direction u get

cos fi= -55.81/229.15

take cos inverse and fi =104.09°

Note : E= initial energy of photon

E'= final energy after scattering of photon

P= momentum of proton