A beam of light travels from sapphire into an unknown material. The angle of incidence is 24o and the angle of refraction is 29.5o. What is the refractive index of the unknown material? What material is this likely to be

When you jump from an elevated position you usually bend your knees upon reaching the ground. by doing this, you make the time of the impact about 10 times as great as for a stiff-legged landing. in this way the average force your body experiences is a) less than 1/10 as great. b) more than 1/10 as great. c) about 1/10 as great.d) about 10 times as great.