Mechanical Quantity vs. Physical Quantity

Attribute	Mechanical Quantity	Physical Quantity
Definition	Related to mechanical systems and their properties	Related to physical properties of matter and energy
Examples	Force, torque, velocity	Mass, temperature, energy
Units	Newtons, Joules, meters per second	Kilograms, Kelvin, Joules
Measurement Devices	Force gauge, dynamometer, speedometer	Thermometer, balance, voltmeter

Definition

Mechanical quantity refers to physical quantities that are directly related to mechanics, such as force, velocity, acceleration, and momentum. These quantities are typically measured using mechanical instruments like scales, rulers, and stopwatches. On the other hand, physical quantity is a broader term that encompasses all measurable properties of physical systems, including mechanical quantities as well as other types of quantities like temperature, pressure, and electric charge.

Units of Measurement

One key difference between mechanical quantity and physical quantity is the units of measurement used to quantify them. Mechanical quantities are typically measured in units like newtons (force), meters per second (velocity), meters per second squared (acceleration), and kilogram meters per second (momentum). Physical quantities, on the other hand, may be measured in a wider range of units depending on the specific property being measured. For example, temperature can be measured in degrees Celsius or Fahrenheit, while pressure can be measured in pascals or atmospheres.

Representation

Another difference between mechanical quantity and physical quantity is how they are represented in equations and calculations. Mechanical quantities are often represented using vectors, which have both magnitude and direction. This is because many mechanical quantities, such as force and velocity, are vector quantities that have both a numerical value and a specific direction in space. Physical quantities, on the other hand, may be represented using scalars, which only have magnitude and no direction. For example, temperature is a scalar quantity that is represented by a single numerical value without any directional component.

Measurement Techniques

When it comes to measuring mechanical quantity and physical quantity, different techniques and instruments are often used. Mechanical quantities are typically measured using mechanical instruments like scales, rulers, and dynamometers. These instruments are designed to accurately measure forces, distances, and times, which are essential for calculating mechanical quantities like velocity and acceleration. Physical quantities, on the other hand, may require different types of instruments depending on the property being measured. For example, temperature can be measured using a thermometer, while pressure can be measured using a manometer.

Applications

Both mechanical quantity and physical quantity have a wide range of applications in various fields of science and engineering. Mechanical quantities are essential for understanding and predicting the behavior of mechanical systems, such as the motion of objects and the forces acting on them. Physical quantities, on the other hand, are used in a broader range of applications, including studying the behavior of gases, liquids, and solids, as well as analyzing the properties of electromagnetic fields and radiation. Overall, both types of quantities play a crucial role in advancing our understanding of the physical world.