Charge Definition: Overview, Questions, Preparation

The electric charge occurs when the force is placed in the electromagnetic field. The physical property of matter is the electric charge. The magnetic field is generated by the electric charge in the electric field and the moving electric charge. When the electric field and the magnetic field are combined and brought together, it's termed an electromagnetic field.

The electric charge can be measured as Q = I.t.

Here, Q = electric charge,

I = electric charge,

And t = time.

 Broadly, there are two types of electric charge, positive and negative electric charge. Protons and electrons carry positive and negative electric charges. Same charges repel each other, and opposite charges attract each other.  The substances that contain no charge whatsoever are called neutral.

1. The positively charged particles are called protons,
2. The negatively charged particles are called electrons,
3. The zero charged particles are called neutrons.

Electric charge is considered as a scalar quantity. Vectors have magnitude and direction, and the electric charge is a scalar quantity because they don't obey vector laws. Vector quantity follows laws of vector-like triangle law of vector or parallelogram law of vector, whereas the same set of rules and laws are not applied to scalar quantities.

Whenever two electric charges meet up at a point, the resultant current will be an algebraic sum of the quantities, not a vector sum. So, even though an electric current possesses magnitude and direction, they are scalar quantities.

The properties of point charge are classified into three parts which are listed below:

1. Additivity of electric charge – let us assume three-point charges each having the magnitude q1, q2, q3 respectively. The total charge can be calculated by adding the three charge:

Q = q1 + q2 + q3

If a system has n particles, the formula can be rewritten as:

Q = q1 + q2 + …. + qn

2. Conservation of electric charge – The conservation of electric charge states that the charges cannot be destroyed or created; they simply can only be transferred from one body to another. The charges are transferred if one object doesn’t have any charge to it, and it comes in contact with an object that has some charge.
3. Quantization of electric charge – The quantisation of electric charge states that the free charges are considered integral multiples of unit e. It can be written as

q = ne

here, n is the integer,

e = unit of charge, the value of c is 1.6 x 10-19 C.

The chapter 'matter and energy' holds a weightage of 6 marks in total. It consists of one objective

type question (1 mark), one very short question (2 marks), and one short question (3 marks).

Example 1) Write the formula of additivity of electric charge.

Answer – The formula is Q = q1 + q2 + …. + qn

Example 2) State the types of electric charge.

Answer – The types of electric charge are

• Positive charge
• Negative charge
• Neutral

Example 3) Write the formula to calculate the electric charge.

Answer – The formula is Q = I.t

Q: How to calculate the quantisation of electric charge?

Q: What do you mean by conservation of electric charge?

Q: What is the meaning of E in electricity?

Q: What is an electric charge?

Q: What is R in electricity?