In solving physics problems, it is often important to use the laws of conservation of energy and momentum. While most people have intuitive understanding of energy and of its conservation, there is usually no intuition behind momentum, and known textbook derivations of conservation of momentum use calculus – which is usually taught after momentum. In this paper, we show how the law of conservat...

A logical error in the usual derivation of the energy conservation law is analyzed, and a way to avoid the error is presented. In earlier papers [1], [2] we identified a logical error adopted by repetition in textbooks on classical electrodynamics when the laws of conservation of energy and momentum are derived for a system consisting of electromagnetic fields and charged particles. In this pap...

We show that Einstein’s gravitational field has zero energy, momentum, and stress. This conclusion follows directly from the gravitational field equations, in conjunction with the differential law of energy-momentum conservation T ;ν = 0. Einstein rejected this conservation law despite the fact that it is generally covariant. We trace his rejection to a misapplication of Gauss’ divergence formu...

From the requirement of continuous matching of bulk metric around the point of brane collision we derive a conservation law for collisions of p-branes in (p+2)-dimensional space-time. This conservation law relates energy densities on the branes before and after the collision. Using this conservation law we are able to calculate the amount of matter produced in the collision of orbifoldfixed bra...

Many physical processes are described by conservative quasilinear systems of equations that admit a supplementary independent conservation law. A typical example is the equations of incompressible fluid dynamics. If for basic equations the conservation laws of the momentum and the volume are chosen then the conservation law of the energy is an additional conservation law. In the present paper a...