Atoms and Nucle...

In Geiger-Marsden experiment prediction was that

Atomic mass unit (u) is defined as ________ of the mass of the carbon (¹²C) atom.

All nuclides with same mass number A are called

If an electromagnetic radiation has an energy of 13.2 keV, then the radiation will belong to the region of

The model that best explains the results of Geiger-Marsden experiment is

Nuclear mass M is found to be

The ionisation energy of 10 times ionised sodium atom is

In Geiger-Marsden experiment, at the point of closest approach

^{_{Consider  particles,  particles and  rays, each having energy of 0.5 MeV. In the increasing order of penetrating power, the radiations are}}

An electron is accelerated from rest to potential V. The final velocity of the electron is

Each element is associated with

For ionising an excited hydrogen atom, the magnitude of energy required (in eV) will be 

According to ‘plum pudding model’ atoms on the whole are electrically neutral because

Mass equivalent to an energy of 931 MeV is

There is a beam of electrons and protons moving parallel to each other in the same direction. Then they

The material used for making thermionic cathode must have

Directions: The following question has four choices out of which ONLY ONE is correct.

Activity of a radioactive sample decreases to (1/3)rd of its original value in 3 days. Then, in 9 days its activity will become

If = 10^-10 m changes to  = 0.5 × 10^-10 m, find the energy difference (E) given to the particle.

What is the radius of the first orbit of H atom? 

Which of these statements correctly describe the atomic model according to classical electromagnetic theory ?

What is the unit of mass when measured on the atomic scale?

The nuclei of isotopes of a given element contain the same number of

Which of the following statements is correct?

A free neutron decays into

Assertion (A): Nuclear forces arise from strong Coulombic interactions between protons and neutrons.
Reason (R): Nuclear forces are independent of the charge of the nucleons.

Bohr's model of an atom

Relation between atomic number (Z), neutron number (N) and mass number (A) is

In the fission of one part of uranium, if 0.5 gm mass is decayed, then how much energy (in kWh) will be obtained?

In Geiger-Marsden experiment very small deflection of the beam was expected because

Nuclides with same neutron number N but different atomic numbers Z are called