Defects in Rutherford’s model

Although Rutherford’s experiment proved that the, plum-pudding, model of an atom was not correct, yet it had following defect:

1.    According to classical theory of radiation, electrons being the charged particles should release or emit energy continuously, they should from a continuous the nucleus.

2.    If the electrons emit energy continuously, they should form a continuous spectrum but in fact, line spectrum was observed.

Although the scientists had objections on the atomic model pres

ented by Rutherford, yet it cultivated thought provoking ideas among them. They initiated the quest to answer the following questions:

1.    How can an atom collapse one why are atoms stable?

2.    Why does an atom give line spectrum?

Scientists considered there must be another model of atom.

It indicated that Rutherford’s model was not perfect.

click here International system of units

International system of units

Measuring is not simply counting. For example, if we need milk or sugar, we must also understand how much quantity of milk or sugar we are talking about. Thus, there is a need of some standard quantities   for measuring\comparing unknown quantities. Once a standard is set for a quantity then it can be expressed in terms of that standard quantity. This standard quantity is called a unit.

       With the developments in the field of science and technology, the need for a commonly acceptable system of unit was seriously felt all over the world particularly to exchange scientific and technical information. The eleventh general conference on weight and measures held in Paris in 1960 adopted a word-wide system of measurements called international system of unit. The international system of unit is commonly referred as SI.

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