# Relativistic Mechanics Notes for Engineering Physics BTech 1st Year

## Relativistic Mechanics Notes for Engineering Physics BTech 1st Year:

The branch of theoretical physics that considers the classical laws of motion of bodies or particles at rates of motion ν comparable with the speed of light. Relativistic mechanics is based on the theory of relativity. The basic equations of relativistic mechanics—the relativistic generalization of Newton’s second law and the relativistic law of conservation of energy-momentum—satisfy the requirements of Einstein’s relativity principle. In particular, it follows from these equations that the speed of material objects cannot exceed c, the speed of light in a vacuum. When ν ≪ c, relativistic mechanics reduces to classical Newtonian mechanics.

## Relativistic Mechanics Definition:

Relativistic mechanics, science concerned with the motion of bodies whose relative velocities approach the speed of light c, or whose kinetic energies are comparable with the product of their masses m and the square of the velocity of light, or mc². Such bodies are said to be relativistic, and when their motion is studied, it is necessary to take into account Einstein’s special theory of relativity. As long as gravitational effects can be ignored, which is true so long as gravitational potential energy differences are small compared with **mc²**, the effects of Einstein’s general theory of relativity may be safely ignored.