An electron and a positron, each having kinetic energy of 0.49 MeV, annihilate after coming to rest in vacuum. Assume that the electron and positron are moving in opposite direction and after annihilation two gamma photons having equal energy are produced. If rest mass energy of electron and position is equal and each have rest mass energy 0.511 MeV, then energy of each gamma photon is nearly
-- 40. The radius of a nucleus with mass number A varies as
NextWhen a p-n junction diode is forward biased, which of the following occurs?
Which of the following is not the unit of length :
Medium-- The speed of light in a medium is 1.5 × 10⁸ m/s. The critical angle for this medium with respect
MediumThe frequency of an electromagnetic wave in free space is 2 MHz. When it passes through a medium of
Easy-- In a p-type semiconductor, the majority charge carriers are
Easy-- The energy of an electron in nth orbit of hydrogen atom is E_n = -13.6/n² eV. The energy required
Medium-- Two magnets of magnetic moments M and 2M are placed in a vibration magnetometer, with like poles
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