PROPERTIES OF ELECTRIC CHARGE

Let us look at the properties was the of electrical charges.

i)                 The “positive” and “negative” adjectives added to the charges are not just for convenience. In fact, the positive and negative are to be treated algebraically, so that net amount of charge produced in any process is zero. This is summarized as law of conversation of charges produced in a process is zero”.

In our previous discussions we saw that the glass rod is positively charged when rubbed with silk. Simultaneously, the silk also develops negative charge on it. The amount of positive charge developed on the glass rod is exactly equal to the amount of negative charge developed on the silk. Thus total charge on the rod and silk is again zero, which was the case before rubbing. This shows that charges are conserved.

ii)             Like charges repel and unlike charges attract each

Other. A charge is a scaler quantity. Since there are two types of charges the addition must be carried with proper sign. For example if there are various charge distributed over a body, then the total charge on the body will be the sum of the individual charge taken with their proper sign. If +4C, -2C, -5C, +6C (C stands for coulomb, unit of charge on SI) are added the total or net charge is +3C. Addition of charges is similar to the addition of positive and negative numerals.

iii)          Charges are quantized. Scientist like R. A. Millikan

Have shown experimentally that the smallest amount of electric charge is found on an electrons and protons. All other electric charge is simply integral multiples of this smallest amount. This fact is called quantization of electrical charge. The charge of the proton is given by symbol ‘e’ and its value in SI units is +1.6×10ˉ19 C. So, charges on an electrons would be -1.6×10ˉ19 C. (More about it in Modern physics part in class XII). Charges, which are fraction of charge on an electrons or a protons gas not been ordinarily observed in nature.