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When it comes to understanding the fundamental units of measurement, there are several key concepts that we need to grasp. These units form the foundation of our understanding of the physical world and are crucial in various scientific disciplines. In this article, we will explore the fundamental units of measurement and identify which of the following is not a fundamental unit.
Understanding Fundamental Units
Fundamental units, also known as base units, are the basic building blocks of measurement. They are independent of each other and cannot be derived from any other units. These units are used to measure physical quantities such as length, mass, time, electric current, temperature, amount of substance, and luminous intensity.
There are seven fundamental units in the International System of Units (SI), which is the most widely used system of measurement in the world. These fundamental units are:
 Meter (m) – for length
 Kilogram (kg) – for mass
 Second (s) – for time
 Ampere (A) – for electric current
 Kelvin (K) – for temperature
 Mole (mol) – for amount of substance
 Candela (cd) – for luminous intensity
Identifying the NonFundamental Unit
Now that we have a clear understanding of the fundamental units, let’s examine the options and identify which of the following is not a fundamental unit:
 Newton (N) – for force
 Ohm (Ω) – for electrical resistance
 Pascal (Pa) – for pressure
 Watt (W) – for power
Newton (N) – The Unit of Force
The Newton (N) is the unit of force in the SI system. It is named after Sir Isaac Newton, the renowned physicist who formulated the laws of motion. The Newton is defined as the force required to accelerate a onekilogram mass by one meter per second squared.
For example, when you push a book on a table, you are applying a force to overcome the friction between the book and the table. This force can be measured in Newtons.
Ohm (Ω) – The Unit of Electrical Resistance
The Ohm (Ω) is the unit of electrical resistance. It is named after Georg Simon Ohm, a German physicist who discovered Ohm’s law, which relates current, voltage, and resistance in an electrical circuit. One Ohm is defined as the resistance that allows one Ampere of current to flow when one Volt of potential difference is applied.
For example, when you use a multimeter to measure the resistance of a resistor in an electronic circuit, the value you obtain will be in Ohms.
Pascal (Pa) – The Unit of Pressure
The Pascal (Pa) is the unit of pressure in the SI system. It is named after Blaise Pascal, a French mathematician, physicist, and philosopher. One Pascal is defined as one Newton of force per square meter of area.
For example, atmospheric pressure at sea level is approximately 101,325 Pascals, which is equivalent to the force exerted by the weight of the Earth’s atmosphere on a onesquaremeter surface.
Watt (W) – The Unit of Power
The Watt (W) is the unit of power in the SI system. It is named after James Watt, a Scottish inventor and mechanical engineer who made significant contributions to the development of the steam engine. One Watt is defined as one Joule of energy transferred per second.
For example, the power rating of a light bulb indicates how much energy it consumes per second, and it is measured in Watts.
Conclusion
In conclusion, the nonfundamental unit among the options provided is the Newton (N). While the Newton is an essential unit for measuring force, it is not one of the seven fundamental units in the SI system. The fundamental units are the meter (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol), and candela (cd). Understanding these fundamental units is crucial for accurate and consistent measurement in various scientific disciplines.
Q&A

 Q: Can fundamental units be derived from other units?
A: No, fundamental units are independent and cannot be derived from any other units. They form the basis for all other units of measurement.

 Q: Are there any other systems of measurement apart from the SI system?
A: Yes, there are several other systems of measurement, such as the Imperial system and the US customary system. However, the SI system is the most widely used and internationally recognized system.

 Q: Why are fundamental units important?
A: Fundamental units are important because they provide a consistent and standardized way of measuring physical quantities. They allow scientists and researchers from different countries and disciplines to communicate and collaborate effectively.

 Q: Can fundamental units change over time?
A: The fundamental units are based on fundamental constants of nature and are considered to be stable and unchanging. However, advancements in scientific knowledge and technology may lead to redefinitions of these units to increase precision and accuracy.

 Q: Are there any proposed changes to the fundamental units in the future?
A: Yes, there have been discussions and proposals to redefine certain fundamental units, such as the kilogram, which is currently based on a physical prototype. The aim is to redefine these units in terms of fundamental constants to ensure their longterm stability and reproducibility.