When light enters a new medium perpendicularly, it does not bend, as indicated by Snell's Law, which states n1 sin(theta1) = n2 sin(theta2). In the case of light transitioning from glass to air, with indices of refraction of 1.5 and 1.0 respectively, the angle of incidence is zero, leading to no change in direction. The discussion raises the question of why light would bend in a specific direction if the medium is isotropic, suggesting that perceived bending could vary based on the observer's position. The conversation emphasizes the importance of understanding the physical properties of the medium when analyzing light behavior. Overall, light entering a new medium perpendicularly remains unaffected in its path.