Find the value of half-life period.
Value of Half-Life Period From the law of radioactive disintegration, we know, If, be the half life period, then at, ,
Day: January 5, 2017
Deduce the law of radioactive disintegration.
The Law of Radioactivity Disintegration: Let, N be the number of atoms present in the radio element at a given instant t. Then the rate of decrease, Here, λ is the disintegration constant. It is defined as the ratio of the amount of the substance which disintegrates in a unit time to the amount of … Read more
Describe the general properties of nucleus.
General Properties of Nucleus: (i) Nuclear Size: From Rutherford’s work, the mean radius of nucleus is and the radius of the atom is . Thus the radius of the nucleus is 10,000 times smaller than the radius of the atom. The empirical formula for the nuclear radius is, Here, A is the mass number, is a constant. From … Read more
Derive the de Broglie wavelength for a charged particle of charge q and accelerated through a potential difference of V volts.
The Required de Broglie Wavelength: A photon of light of frequency has the momentum, But, . Therefore, the momentum of the photon can be expressed in terms of wavelength λ as, The wavelength of a photon is, therefore, specified by its momentum according to the relation, de Broglie suggested that the above equation is applicable for any … Read more
Derive the Einstein’s photoelectric equation.
Einstein’s Photoelectric Equation : According to Einstein, light of frequency consists of a shower of photons, is of energy . When a photon of light of frequency is incident on a metal, a part of the energy acquired by the electron is used to pull out the electron from the surface of the metal and the rest of … Read more