If a stationary electron gets annihilated due to the association with a stationary positron (hypothetically), the wavelength of the resulting radiation will be
where rest mass of an electron (or positron)
None of these
Conserving the momenta of the system just before and after the event (anhiliation) we see that two identical photons will be resulted and travel in opposited directions with equal magnitude of momenta and energy where
wavelength of radiation.
Conservation of energy yields,
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5 g of Na2SO4 was dissolved in x g of H2O. The change in freezing point was found to be 3.820C. If Na2SO4 is 81.5% ionised, the value of x (K

A capacitor is made of two square plates each of side 'a' making a very small angle
A solution of m-chloroaniline, m-chlorophenol and m-chlorobenzoic acid in ethyl acetate was extracted initially with a saturated solution of NaHCO3 to give fraction A. The leftover organic phase was extracted with d