Consider an optical disk drive with a lens focusing a collimated beam into a mm-thick disk with an index of refraction of n. If disk moves towards the lens a distance, t, how much does the focus shift inside the material? Assume the paraxial approximation and that the focus remains inside the material (i. e. t is not far enough to move the focus past the material). Express your answer in terms of the two given variable

The intensity of a polarized electromagnetic wave is 12 w/m^2. part a) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=0∘ with the plane of polarization? part b) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=30∘ with the plane of polarization? part c) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=45∘ with the plane of polarization? part d) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=60∘ with the plane of polarization? part e) what will be the intensity after passing through a polarizing filter whose axis makes the angle θ=90∘ with the plane of polarization?

Which of the following is the phase that results when the moon is on the opposite side of the earth from the sun? a. quarter moon b. crescent moon c. new moon d. full moon

Give an example of a collision in real life. use the law of conservation of energy to describe the transfer of momentum. be sure and discuss the momentum before and after the collision occurs. you will need at least 3 sentences to thoroughly answer this question.