Question and Answers Forum

All Questions      Topic List

Moderm Physics Questions

Previous in All Question      Next in All Question      

Previous in Moderm Physics      Next in Moderm Physics      

Question Number 45646 by rahul 19 last updated on 15/Oct/18

$$Accordingtorelativistictheory,$$$$E^2=p^2{c}^2+m_0^2{c}^{4}where{m}_{0}isrestmass.$$$$ForphotonE=pc...$$$$(m_0=0forphoton)$$$$ForelectronE={mc}^2...$$$$Unlikephoton,Why{p}^2{c}^{2}isneglected$$$$incaseofelectron?$$

Commented by hassentimol last updated on 15/Oct/18

$$$$$$$$$$\mathrm{For}\mathrm{photons},\mathrm{the}\mathrm{mass}\mathrm{is}\mathrm{equal}\mathrm{to}0.$$$$\mathrm{So},0^2\times {\mathrm{c}}^2=0,\mathrm{so}\mathrm{this}\mathrm{part}\mathrm{is}\mathrm{neglected}\mathrm{for}\mathrm{that}\mathrm{reason}.$$$$$$$$\mathrm{The}\mathrm{mass}\mathrm{of}\mathrm{an}\mathrm{electron},\mathrm{is}\mathrm{not}\mathrm{null}\mathrm{indeed},$$$$\mathrm{however},\mathrm{as}\mathrm{it}\mathrm{is}\mathrm{a}\mathrm{very}\mathrm{small}\mathrm{number},$$$$\mathrm{the}\mathrm{number}\mathrm{become}\mathrm{smaller}\mathrm{while}\mathrm{being}$$$$\mathrm{squared}\mathrm{thought}\mathrm{it}\mathrm{is}\mathrm{multiplied}\mathrm{by}\mathrm{the}\mathrm{square}$$$$\mathrm{of}\mathrm{the}\mathrm{celerity}.$$$${\mathrm{That}}^{\prime }\mathrm{s}\mathrm{why}\mathrm{it}\mathrm{is}\mathrm{neglected}\mathrm{and}\mathrm{must}\mathrm{be}\mathrm{an}$$$$\mathrm{aproximate}\mathrm{answer}\mathrm{and}\mathrm{not}\mathrm{an}\mathrm{exact}\mathrm{one}.$$

Commented by rahul 19 last updated on 15/Oct/18

$$thankssir.$$

Terms of Service

Privacy Policy

Contact: info@tinkutara.com