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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) – for Force
The Newton (N) is the unit of force in the SI system. It is defined as the force required to accelerate a onekilogram mass by one meter per second squared. The Newton is derived from the fundamental units of kilogram, meter, and second. Therefore, the Newton is a derived unit and not a fundamental unit.
Ohm (Ω) – for Electrical Resistance
The Ohm (Ω) is the unit of electrical resistance in the SI system. It is defined as the resistance between two points of a conductor when a constant potential difference of one volt, applied to these points, produces a current of one ampere. The Ohm is derived from the fundamental units of kilogram, meter, and second. Therefore, the Ohm is a derived unit and not a fundamental unit.
Pascal (Pa) – for Pressure
The Pascal (Pa) is the unit of pressure in the SI system. It is defined as one newton per square meter. The Pascal is derived from the fundamental units of kilogram, meter, and second. Therefore, the Pascal is a derived unit and not a fundamental unit.
Watt (W) – for Power
The Watt (W) is the unit of power in the SI system. It is defined as one joule per second. The Watt is derived from the fundamental units of kilogram, meter, and second. Therefore, the Watt is a derived unit and not a fundamental unit.
Summary
In conclusion, the nonfundamental unit among the options provided is the Newton (N) for force. While the Newton is an important unit for measuring force, it is derived from the fundamental units of kilogram, meter, and second. The fundamental units in the SI system are the meter (m), kilogram (kg), second (s), ampere (A), kelvin (K), mole (mol), and candela (cd). Understanding these fundamental units is essential for accurate and consistent measurement in various scientific disciplines.
Q&A

 Q: Can derived units be used interchangeably with fundamental units?
A: Yes, derived units can be used interchangeably with fundamental units as long as the conversion factors are applied correctly.

 Q: Are there any other derived units in the SI system?
A: Yes, there are several other derived units in the SI system, such as the volt (V) for electric potential, the coulomb (C) for electric charge, and the hertz (Hz) for frequency.

 Q: Why are fundamental units important?
A: Fundamental units are important because they provide a consistent and standardized way of measuring physical quantities. They form the basis for scientific calculations, experiments, and comparisons.

 Q: Can fundamental units change over time?
A: The fundamental units are based on internationally agreedupon standards and are subject to periodic redefinitions to ensure their accuracy and precision. However, any changes are carefully implemented to maintain continuity and compatibility with existing measurements.

 Q: Are there any exceptions to the fundamental units?
A: In certain specialized fields, such as atomic and nuclear physics, different systems of units may be used. These systems may have additional fundamental units specific to those fields.