The flux of one element must have _________ to the flux of the neighbouring element.
(a) different magnitude and equal sign
(b) different magnitude and opposite sign
(c) equal magnitude and equal sign
(d) equal magnitude and opposite sign
This question was posed to me in an international level competition.
My doubt is from Discretization Aspects in chapter Basic Aspects of Discretization, Grid Generation with Appropriate Transformation of Computational Fluid Dynamics