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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
Out of these options, the nonfundamental unit is the Newton (N) for force. While force is an essential physical quantity, it is not considered a fundamental unit because it can be derived from the fundamental units of mass, length, and time. The Newton is defined as the force required to accelerate a onekilogram mass by one meter per second squared.
Examples and Applications
To further illustrate the concept, let’s explore some examples and applications of the fundamental units and the nonfundamental unit:
Example 1: Force Calculation
Suppose we have a box with a mass of 10 kilograms. To calculate the force required to accelerate the box at a rate of 5 meters per second squared, we can use the formula:
Force (N) = Mass (kg) × Acceleration (m/s²)
Using this formula, we can calculate the force as:
Force = 10 kg × 5 m/s² = 50 N
Here, we can see that the force is measured in Newtons (N), which is derived from the fundamental units of mass (kg) and acceleration (m/s²).
Example 2: Electrical Resistance
Electrical resistance is a crucial concept in electrical engineering. It is measured in Ohms (Ω), which is not a fundamental unit. The Ohm is derived from the fundamental units of voltage (V) and current (A) using Ohm’s Law:
Resistance (Ω) = Voltage (V) / Current (A)
By manipulating the fundamental units, we can derive the unit of electrical resistance, which is the Ohm (Ω).
Summary
In conclusion, the nonfundamental unit among the options provided is the Newton (N) for force. While force is an essential physical quantity, it can be derived from the fundamental units of mass, length, and time. The fundamental units, such as the meter, kilogram, second, ampere, kelvin, mole, and candela, form the foundation of measurement in the International System of Units (SI). Understanding these fundamental units is crucial for various scientific disciplines and applications.
Q&A
1. What are 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.
2. How many fundamental units are there in the International System of Units (SI)?
There are seven fundamental units in the International System of Units (SI). These fundamental units are the 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, and candela (cd) for luminous intensity.
3. Which of the following is not a fundamental unit?
The nonfundamental unit among the options provided is the Newton (N) for force. While force is an essential physical quantity, it can be derived from the fundamental units of mass, length, and time.
4. How is the Newton (N) derived from the fundamental units?
The Newton (N) for force is derived from the fundamental units of mass (kg), length (m), and time (s). It is defined as the force required to accelerate a onekilogram mass by one meter per second squared.
5. Can you provide an example of a nonfundamental unit and its derivation?
One example of a nonfundamental unit is the Ohm (Ω) for electrical resistance. The Ohm is derived from the fundamental units of voltage (V) and current (A) using Ohm’s Law: Resistance (Ω) = Voltage (V) / Current (A).