Name the part of a spherical mirror, when a light ray incident on which is reflected by making equal angles with the principal axis.

the electric field is a “force field” around a charged object that illustrates the direction the electric force would push an imaginary 

jupiter is the largest planet in our solar system, having a mass and radius that are respectively, 318 and 11.2 times that of earth. suppose that an object falls from rest near the surface of each planet and that the acceleration due to gravity remains constant during the fall. each object falls the same distance before striking the ground. determine the ratio of the time of fall on jupiter to that on earth.