Physics
Physics
Problem
A pyramid has four faces, all of them being equilateral triangle of side . A charge is placed at the centre of one of the faces. What is the flux of electric field emerging from any one of the other three faces of the pyramid?Intuitive explanation
This is a problem about solid angle and Gauss's law—the key insight is that electric flux through a surface depends only on the solid angle it subtends at the charge's location, not its shape or distance. Since the charge sits on one face of a regular tetrahedron, the three remaining faces together subtend a specific solid angle. By symmetry and the fact that all flux must exit through these three faces (none through the base where the charge sits), you can find what fraction of the total flux passes through each one.
Intuitive explanation
This is a problem about solid angle and Gauss's law—the key insight is that electric flux through a surface depends only on the solid angle it subtends at the charge's location, not its shape or distance. Since the charge sits on one face of a regular tetrahedron, the three remaining faces together subtend a specific solid angle. By symmetry and the fact that all flux must exit through these three faces (none through the base where the charge sits), you can find what fraction of the total flux passes through each one.