[2] A radioactive nucleus x decays to a nucleus y with a decay constant x = 0.1 s-1 y further decays to a stable nucleus z with a decay constant y = 1/30. Intially, there are only x nuclei and...

(2) A small Quantity of solution containing Na-24 radioactive nuclei t1/2 = 15h of activity 1.0 ci is injected into the blood of a person. A sample of blood of volume 1cm3 taken after 5th, throws...

(6) In an experiment on 2 radio active isotope of an elment which do not decay in to each other, mass ratio at a given instance was 3:1. That rapidly decaying isotope has larger mass & activity...

Units of activity:- s1 units of activity is Becqueral(Bq) other commonly units are curve (c1) and ratherford(rd) 1Bq = 1 decay/s 1Ci =3.7 X 1010 Bq 1rd = 106 Bq PROBLEMS Easy At time = 0,...

Radioactive decay process follows first order Kinetics i.e rate of reaction depends upon no. of nucleus raised to power one. where disintegration / decay constant. or Integrating both...

Nuclear Fusion:- the process of combining two light nuclei to form a heavy nucleus is known as nuclear fusion when two light nuclei (having low binding energy the nucleon)are combined to form a...

Introduction Nucleus the central core of an atom is held together by a short -range force called nucleus force, which is also a potential source of energy called Nuclear energy. in this unit we...

HARD:- 1. An imaginary particle has a charge equal to that of an electron and mass 100 times the man of the electron. If moves in a circular orbit around a nucleus of charge + 4e. Take the mass of...

2. A Hydrogen like atom of atomic Z is in an excited state of quantum number 2n. It can emit a maximum energy photon of 204 eV. If it makes a transition of quantum state n, a photon energy 40.8 eV is...

5. Calculate the second excitation potential of helium. Given e = 1.6 X 10-18C, m = 9.1 X 10-31Kg. Solution:- Energy of first orbit, E1 = 36.6 z2 Energy of third orbit, E3 = Third excilation...

MOSELEY'S LAW FOR CHARACTERISTIC X-RAY:- Moseley measured the frequency of characteristic X-rays from a large number of elements and plotted the Vs Z. The plot was close to a straight line...

few handy difinations:- IONIZATION POTENTIAL:- The minimum energy needed to ionize an atom is called ionization energy, and the potential defference through which an electron should be accelerated...

Bohr Energy levels:- The energy of a revolving electron is :- (i) Kinetic Energy, due to its revolution in the orbit. (ii) Electrostatic Potential Energy. The total energy Eu is the sum of...

Physics: Modern Physics Neils Bohr gave forward his model of atom with answeres most of the flaws that Rutherford model had. This model introduced quantization principal and this model is regarded...

HARD TYPE Q.1. 1.8g H - atoms are excited to radiation. Spectra shows that 27% of atoms are in IIIrd energy level & 1.5% of atoms in IInd energy level & rest in ground state. Ionization...

Q.3. Wave function of 2s electron is given by . It has node at r = r0. Find relation b/w r0 & a0. Ans:          225 = 0 at r = r0 [Dumb Question:...

Rule for finding Group No.: (i) If last shell contains 1 or 2 electrons, then group no. is 1 & 2 respectively. (ii) If last shell contains more than 2 elctrons in last shell plus....

Shape of p-orbital: Shape of p-orbital is dumb bell shape. Note: No. of spherical/radial nodes in any orbital = n - -1 No. of planar nodes in any orbital = In s-orbital, spherical nodes...

Size of nucleus: Size of nucleus (r) = (1.3 x 10-13) m1/3 r rad. of nucleus     m Atomic no. Dumb Question: Why radius of nucleus varies m1/3 i.e. r m1/3 ? Ans: If...

Calculation of de broglie wavelength of electron from potential applied to accelerate it: If accelerating potential v is applied, Energy by electron = ev (charge x potential = ....)...