An Electron-positron Pair Is Produced By The Materialization Of A Gamma-ray Photon Of 2.26 MeV. How Much Kinetic Energy Is Imparted To Each Of The Charged Particle? The Rest Mass Of Elector Is  and The Speed Of Light is . Take .

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Question

An electron-positron pair is produced by the materialization of a gamma-ray photon of 2.26 MeV. How much kinetic energy is imparted to each of the charged particle? The rest mass of elector is  and the speed of light is Take .

Solution

Correct option is

0.62 MeV

The equation representing pair-production is

        

        (electron)         (positron) 

The rest-mass of electron-positron pair is 

       

            

              

            = 1.02 MeV. 

For electron-positron pair-production, the minimum energy of -photon should be 1.02 MeV. The energy in excess of this is imparted as kinetic energy to both these particles. 

Here, the excess energy of the -photon is 2.26 MeV – 1.02 MeV. Thus, on the average, the kinetic energy imparted to each particle is 0.62 MeV. In fact, the positron gates slightly more than half.   

Testing

SIMILAR QUESTIONS

Q1

The normal activity of a living mater containing radioactive carbon C14 is found to be 15 decays per minute per gram of carbon. An archaeological specimen shows an activity of 9 decays per minute per gram of carbon. Estimate the age of the specimen. The half-life of C14 is 5730 years.

Q2

A radioactivity sample contains 2.2 mg of pure  which has half-life period of 1224 seconds. Calculate the number of atoms present initially.

Q3

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Q4

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Q5

A radioactive isotope X has a half-life of 3 seconds. At t = 0 second, a given sample of this isotope X contains 8000 atoms. Calculate the number of decays per second in the sample at t = t1 second.    

Q6

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Q7

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Q8

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Q9

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Q10

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