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Newton vs Joule


To understand Newton vs Joule, we need to comprehend the concept of force and energy. Two important units of measurement associated with these concepts are the newton and the joule. Therefore, understanding the difference between newton and joule is important to comprehend various phenomena and calculations in physics.

In this comprehensive guide, we will explore the distinction between newton and joule, their applications, and their significance in the realm of physics.

Newton: The Measure of Force

What is a Newton?

A newton (N) is the standard unit of force in the International System of Units (SI). It is named after Sir Isaac Newton, the renowned physicist who laid the foundations of classical mechanics. One newton is defined as the force required to accelerate a one-kilogram mass by one meter per second squared.

Applications of Newton

The newton is commonly used to describe forces in various contexts, including:

  1. Mechanical systems: It quantifies the force exerted on objects due to interactions between them. For example, the force we need to push a heavy box or lift a weight is in newtons.
  2. Engineering: We use Newtons in structural analysis to calculate the forces acting on structures like bridges, buildings, and machinery.
  3. Astronomy: Newtons are instrumental in studying celestial bodies and their interactions. They help determine the gravitational forces between planets, stars, and galaxies.

Newton vs Joule

Newton vs Joule
Newton vs Joule
  1. Field of Study: Isaac Newton and James Joule made significant contributions to different fields of study. Newton was a physicist and mathematician who developed the laws of motion and universal gravitation, while Joule was an experimental physicist who focused on the study of energy and thermodynamics.
  2. Laws and Principles: Newton formulated the three laws of motion, which describe the relationship between a body and the forces acting upon it. In contrast, Joule’s work revolved around the principles of energy conservation and the relationship between heat and mechanical work.
  3. Units of Measurement: Newton is associated with the unit of force named after him, the newton (N). This unit measures the amount of force required to accelerate a mass of one kilogram at a rate of one meter per second squared. On the other hand, Joule’s name is associated with the unit of energy, the joule (J), which measures work and energy transfer.
  4. Discoveries: Newton is renowned for his discovery of the laws of motion and universal gravitation, which laid the foundation for classical mechanics. He also developed calculus independently. In contrast, Joule’s notable contributions include the formulation of the law of conservation of energy and the determination of the mechanical equivalent of heat.
  5. Time Period: Newton lived from 1643 to 1727, primarily during the 17th and 18th centuries. His work was influential during the scientific revolution. James Joule, on the other hand, lived from 1818 to 1889 and made his significant contributions during the 19th century, which was marked by advancements in industrialization and the study of energy.

Example Calculation: Force in Newtons

Let’s consider a scenario where a person pushes a 10-kilogram box with a force of 20 newtons. To determine the acceleration, we can use Newton’s second law of motion:

F = m x a

where F represents the force, m denotes the mass, and a signifies the acceleration. Rearranging the equation, we have:

a = F / m

Plugging in the values, we get:

a = 20 N / 10 kg = 2 ms-2

Thus, the acceleration of the box is 2 meters per second squared.

Joule: The Measure of Energy

What is a Joule?

A joule (J) is the standard unit of energy and work in the International System of Units. It is named after James Prescott Joule, a British physicist who contributed significantly to the study of energy. We can define one joule as the amount of energy expended when a force of one newton acts over a distance of one meter.

Applications of Joule

The joule finds widespread use in measuring and calculating various forms of energy, including:

  1. Mechanical energy: It quantifies the energy possessed by an object due to its motion or position. For instance, the potential energy of an elevated object and the kinetic energy of a moving object are measured in joules.
  2. Electrical energy: We use joules to determine the energy consumed or produced by electrical devices. They help calculate power consumption, battery capacity, and the efficiency of electrical systems.
  3. Thermal energy: We also use joule to measure the amount of heat transferred or stored in a system. It aids in understanding heat flow, specific heat capacities, and temperature changes.

Example Calculation: Work Done in Joules

Let’s consider a scenario where a person lifts a 20-kilogram box to a height of 5 meters. To calculate the work done, we can use the equation:

W = F x d

where W

represents the work done, F denotes the force applied, and d signifies the distance moved. Rearranging the equation, we have:

F = m x g

where m represents the mass of the box and g signifies the acceleration due to gravity (approximately 9.8 m/s²). Substituting the values, we get:

F = 20 kg x 9.8 m/s² = 196 N

Now, we can calculate the work done:

W = 196 N x 5m = 980 J

Therefore, the work done in lifting the box to a height of 5 meters is 980 joules.

Newton vs Joule: Understanding the Difference

Different Measurements

The fundamental difference between newton and joule lies in their measurement. A newton quantifies the force applied to an object, while a joule measures the energy expended or transferred by a force.

Force vs Energy

Force refers to the push or pull applied to an object, influencing its motion or deformation. Energy, on the other hand, represents the capacity of an object or system to perform work or produce heat.

Calculation vs Result

We use Newton to calculate forces acting on objects. On the other side, we use joule to measure the work done or the energy involved in a physical process.

Relationship Between Newton and Joule

The relationship between newton and joule is work. When a force of one newton acts over a distance of one meter, it results in the transfer or expenditure of one joule of energy.

FAQs (Frequently Asked Questions)

Q1: Can a newton and a joule be used interchangeably?

No, we cannot use newtons and joules interchangeably. Newtons measure force, whereas joules measure energy. They serve different purposes in physics.

Q2: Can you convert newtons to joules?

No, we cannot directly convert newtons and joules into each other since they measure different aspects of physics. Newtons quantify force, while joules quantify energy.

Q3: Is it possible to have a force without energy?

No, there is a relationship between forces and energy. Whenever a force is applied, energy is either expended or transferred. Therefore, forces are associated with energy in various forms.

Q4: Are there any other units to measure force and energy?

Yes, apart from newtons, we can measure force in other units like pounds, dynes, or kilogram-force. Similarly, we can also measure energy in units such as calories or electronvolts.

Q5: How are newtons and joules related to other units of measurement?

Newtons are related to kilograms and meters through Newton’s second law of motion, while joules are related to newtons and meters through the work-energy principle.

Q6: Can you give an example where both newtons and joules are involved?

Certainly! When a person pushes a car with a force of 500 newtons over a distance of 10 meters, we can calculate the work done in joules using the formula W = F * d. Therefore, W = 500 x 10 = 5000 Joules.


In conclusion, the knowledge of newton vs joule is important in the field of physics. Newtons quantify force, whereas joules measure energy. Therefore, understanding their difference is important for comprehending various physical phenomena, calculations, and real-world applications. Knowing the distinction between newton and joule, you can go deeper into the beautiful world of physics and appreciate the underlying principles that govern our universe.

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