The Body Mass Index (BMI) is a numerical value derived from a person's weight and height, used to categorize individuals into weight ranges. It is calculated using the formula: weight in kilograms divided by height in meters squared. Obesity is a health condition characterized by excessive accumulation of adipose tissue that poses health risks, often diagnosed with a BMI ≥ 30. This excess fat storage occurs when surplus dietary calories are converted into triglycerides and stored in...

Mass and weight are often used interchangeably in everyday conversation. For example,  medical records often show our weight in kilograms, but never in the correct units of newtons. In physics, however, there is an important distinction. Weight is the pull of the Earth on an object. It depends on the distance from the center of the Earth. Weight dramatically varies if we leave the Earth's surface, unlike mass, which does not vary with location. On the Moon, for example, the...

Atoms — and the protons, neutrons, and electrons that compose them — are extremely small. For example, a carbon atom weighs less than 2 × 10−23 g. When describing the properties of tiny objects such as atoms, we use appropriately small units of measure, such as the atomic mass unit (amu). The amu was originally defined based on hydrogen, the lightest element, then later in terms of oxygen. Since 1961, it has been defined with regard to the most abundant isotope of carbon, atoms of which...

The mass moment of inertia is a measure of the resistance of a rigid body to angular acceleration. This physical quantity can be evaluated and analyzed in various rotational motions, from everyday objects such as fans and wind turbines to complex machines used in challenging industries.
Consider a differential mass element on an arbitrary object. The differential moment of inertia can be calculated by multiplying the mass of the element by the square of its distance from the object's rotational...

Knowing how to determine the moment of inertia in a wheel's axle can be invaluable in engineering and automotive applications. It provides an understanding of how changes in geometry, mass, and radius can impact its performance.
The axle can be approximated to a solid cylinder with longitudinal and perpendicular axes. Initially, a thin disc is considered parallel to the circular face of the cylinder.

The human body is a powerhouse of energy, with every cell performing numerous functions that require energy. This energy production and consumption is measured by the metabolic rate, which quantifies the total heat generated by all the body's chemical reactions and mechanical work. This measurement helps to determine the rate of kilocalorie (kcal) consumption needed to fuel all ongoing activities.
The Basal Metabolic Rate (BMR) measures the energy expended at rest.
Several factors influence...