Question
Question: All free electric charges can be (e= single unit of charge i.e. the magnitude of charge on electr...
All free electric charges can be
(e= single unit of charge i.e. the magnitude of charge on electron )
(A) Odd multiples of e
(B) Fraction multiples of e
(C) even multiples of e
(D) Negative multiples of e
Solution
The concept of quantization of charge will be followed here, which means that the charge cannot take any arbitrary value, but only values which are integer multiples of the fundamental charge i.e, q will not be equal to 0.8 or 1.4 or 7.9 but it will 0,1,7. So, the charge can’t be a fraction.
Complete answer:
The charges are acquired either by gain or by loss of electrons. And electron transfer can only happen as integers, electron fraction cannot be shared. Therefore, the load on a body can be a positive or negative integer multiple of e.
Hence, option A, C and D is correct.
Additional Information: Quantization simply means that the values are not continuous but rather discrete. For example, the weight is continuous because we can weigh anything up to any decimal point we want.
Specifically, by saying that charges are quantized, we are saying that charges cannot reach any value (unlike weight - if we think of a number, it could be the weight of an arbitrary object). The charges are quantified because the charges of any object (ion, molecule, etc.) are multiples of a fundamental quantity.
Charge can be expressed as Q = ne
Where n is an integer, while eis the fundamental unit of charge - or the elementary charge. The value of e is the charge of the electron / proton (they differ only by the sign) which is approximately
1.602 × 10−19 Coloumbs.
Note: Charges are not created or destroyed, they can only be transferred from one system to another. Materials that allow electrons to move freely through them, such as most metals. Electricity charges are of two general types: positive and negative. Two objects that have more than one type of charge exert repulsive force on each other when they are relatively close to each other. Two objects that are in excess of the opposite charge, one positively charged and the other negatively charged, attract each other when relatively close.