Essential Biomechanics Formulas and Human Motion Principles

Core Biomechanics Formulas for Human Motion Analysis

1. Kinematics (Motion Without Forces)

Kinematics describes motion without considering the forces that cause it.

Key Linear Formulas:

  • Displacement (Δx):

    Δx = x₂ − x₁

    Example: If a sprinter moves from 2 m to 8 m → Δx = 6 m

  • Velocity (v):

    v = Δx / Δt

    Example: 6 m in 2 s → v = 6 / 2 = 3 m/s

  • Acceleration (a):

    a = Δv / Δt

    Example: Speed changes from 2 m/s to 6 m/s in 2 s → a = (6−2)/2 = 2 m/s²

Angular Motion Formulas:

  • Angular Displacement (θ)
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Physics Fundamentals: Work, Heat Transfer, and Electrical Circuit Calculations

Work, Power, and Energy Calculations

  • Work Done Lifting a Load

    Question: How much work is done in lifting a 500 kg load to a height of 40 m?

    Answer: 1.96 × 108 J

  • Motor Power Calculation

    Question: How powerful is a motor that can lift a 1200 kg load 10 m in 20 s?

    Answer: 5886 Watts

  • Work and Lifting Height

    Question: Which of the following statements is true regarding the work associated with lifting a box to a certain height?

    Answer: All of these will require the same amount of work.

  • Law of Conservation of

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Historical Development of Planetary Motion Theories

1. Ptolemy’s Geocentric Model (2nd Century)

  • Model geocentric: the Earth is at the center of the universe.
  • All the planets and fixed stars move in circular orbits around the Earth.
  • To explain the motion of the planets against the background of fixed stars (retrograde motion), it was necessary to introduce epicycles and deferents.
  • Although mathematically complicated, the model fit well with observations and could be applied practically (navigation, predicting eclipses, etc.).

2. Copernicus and the Heliocentric

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The Physics of Light: Reflection, Refraction, and Vision

Fundamentals of Light and Optics

Light is a form of electromagnetic radiation, composed of both electric and magnetic fields that oscillate perpendicularly to each other. It travels in straight lines and is a fundamental form of energy that can be reflected, refracted, and absorbed.

Core Properties of Light

  • Light travels at an incredible speed: 299,792,458 meters per second (approximately 186,282 miles per second) in a vacuum.
  • Light is a form of energy that can be reflected, refracted, and absorbed.
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Fundamental Concepts in Applied Physics and Fluid Dynamics

Q.Explain the construction and working of Ruby laser with the help of energy level diagram


Ruby is a crystal of aluminum oxide Al2O3 in which chromium Cr3+ ions are added as impurity (0.5%).So its colour is pink. Ruby rod of 4cm in length and 0.5 cm in diameter is generally used. The end faces of rod are strictly made parallel, grounded and silver polished. The one end face is fully reflecting and other end is partially reflecting. A helical Xenon flash tube is surrounded the ruby rod with high voltage

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Core Concepts in Physics: Energy, Forces, and Circuits

Energy and Work Done

Defining Work, Power, and Energy

  • Work Done: Energy transferred when a force moves an object over a distance.
  • Power: The rate at which energy is transferred (how quickly).
  • Energy Stores: Kinetic, gravitational potential, elastic potential, thermal, chemical, and nuclear.
  • Energy Transfers: Occur via mechanical work, electrical work, heating, and radiation.

Efficiency in Energy Transfer

The higher the efficiency, the less energy is wasted (often as heat or sound).

Note: No machine is 100%

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