Question

suppose that a particle at rest with mass m decays into a photon and another particle with mass m/2 , which recoilds in a direction opposite to the photon. Using the conservation of energy and momentum find the momentum of the recoiling particle

Answer 1

`p_r=(h)/(\lambda)`

Step-by-step explanation:

To find the momentum of the recoiling particle you can use the momentum formula for a photon:

`p=(h)/(\lambda)`

before the decay the momentum is zero. Hence, after the decay the momentum of the photon plus the momentum of the recoiling particle must be zero:

`p_a=p_b\\\\(h)/(\lambda)-(m)/(2)v=0\\\\p_r=(m)/(2)v=(h)/(\lambda)`

where pr is the momentum of the recoiling particle.