Compare the bending of the paths of baseballs and photons by a gravitational field.
Solution Step 1 of 3 The bending of path of the baseball by gravitational field, If a baseball is thrown in space far away from the earth surface(where there is no gravitational field), it will travel in a straight line at constant speed. Similarly on the earth surface If the same baseball is thrown, the straight line gets bent so that the ball falls down after reaching maximum height due to gravitational downward pull of earth. The trajectory of baseball will trace a parabolic path,which is bent a straight line. Step 2 of 3 The bending of the path of the photon by gravitational field, Light consists of a large number of energy qantas which are known as photons. The phenomenon of bending of photon or the light ray path due to the gravitational field of sun, is referred as gravitational lensing. If we observe a star location during day time, the rays from the star will be bent due to the gravitational field of sun and hence the star will appear at apparent location. As in the figure, Whereas if we observe the same star during night time,as the light rays will not be bent by the sun; the location of the star will be at actual position. As in the figure, According to Einstein,the paths that light(photons) takes are "straight", and it's really space and time that are "bent".