The question asks to identify the two distinct types of electric charge, which is a fundamental concept in physics. We need to recall the basic classification of electric charges.
Correct Option: A) Electric charge exists in two distinct types: positive and negative. These are the fundamental classifications used in physics to describe the electrical property of matter.
The question asks for the SI unit of electric charge. We need to identify the correct unit among the given options and understand what each of the other units represents.
Electric charge is a fundamental property of matter. The SI (International System of Units) unit for electric charge is the Coulomb.
One Coulomb is defined as the amount of charge transported by a constant current of one Ampere in one second. Mathematically, this can be expressed as:
\[ Q = I \times t \]Where \(Q\) is the charge in Coulombs, \(I\) is the current in Amperes, and \(t\) is the time in seconds.
A) Coulomb — The Coulomb (C) is indeed the SI unit of electric charge. It is named after the French physicist Charles-Augustin de Coulomb.
The question asks about Coulomb's Law, which describes the electrostatic force between two point charges. We need to recall the mathematical formulation of Coulomb's Law to determine the correct relationship between the force, the charges, and the distance between them.
Correct Option: D) Directly proportional to the product of the two charges and inversely proportional to the square of the distance between them.
This statement perfectly matches the mathematical formulation of Coulomb's Law, \(F \propto \frac{|q_1 q_2|}{r^2}\).
The question asks for the correct definition of an electric field. We need to understand what an electric field represents and how it interacts with other charges or materials.
Correct Option: C) Any other charge placed within this region will experience a force
The question asks for the definition of electric field intensity (or electric field strength) at a point. This is a fundamental concept in electrostatics. The definition involves the force experienced by a specific type of charge.
Understanding Electric Field: An electric field is a region around a charged particle or object within which a force would be exerted on other charged particles or objects.
Defining Electric Field Intensity: Electric field intensity, denoted by \( \vec{E} \), at a point is defined as the electric force \( \vec{F} \) per unit charge experienced by a test charge \( q_0 \) placed at that point.
Mathematical Formulation: The formula for electric field intensity is given by:
\[ \vec{E} = \frac{\vec{F}}{q_0} \]Here, \( \vec{F} \) is the force experienced by the test charge \( q_0 \).
Properties of the Test Charge: For the definition to be consistent and to accurately measure the field produced by the source charge without disturbing it, the test charge \( q_0 \) must have two key properties:
Conclusion: Therefore, electric field intensity is defined as the force experienced by a unit positive charge placed at that point.
Correct Option: D) A unit positive charge placed at that point
The question asks about the characteristics of an electric field intensity in a 'uniform' electric field. Understanding the definition of a uniform electric field is key to answering this question.
Correct Option: A) The same in both magnitude and direction at every point within the field
This statement directly matches the definition of a uniform electric field. In a uniform electric field, the electric field intensity vector \( \vec{E} \) is identical (same magnitude and same direction) at all points within that field.