This Demo lesson includes the introduction to one of the highest weightage chapters of Physics inboards

ATOMS

• Starting from Rutherford's nuclear model of an atom to the alpha particle trajectory, physics observes it's conclusions from points to derivations ( mentioning the derivation of the two forces in a hydrogen atom here) to atomic spectra. There have been various experiments mentioned in this chapter that is about to be discussed. 

1. First, Thomson's model concluded that an atom is a spherical cloud of positive charges with electrons embedded in it. But since the information wasn't enough, Rutherford came with his nuclear model of an atom. In it,  most of the mass of the atom and all its positive charge is concentrated in a tiny nucleus (typically one by ten thousand the size of an atom), and the electrons revolve around it.
2. Drawbacks of Rutherford's model : 

• It predicts that atoms are unstable because the accelerated electrons revolving around the nucleus must spiral into the nucleus. This contradicts the stability of matter.
• It cannot explain the characteristic line spectra of atoms of different elements.

 3. Atomic Spectrum :

• Lyman series 
• Balmer series
• Paschen series
• Brackett series
• Pfund series