Homework Assignment Geometric Optics

11/16/23, 6:27 PM Homework 7: Geometric Optics: Attempt review Question 3 Correct Mark 0.00 out of 1.00 Refer to the previous problem about the glass hemisphere in a fluid. The beam of light enters the flat surface at the exact centre of the glass hemisphere, and exits the glass at the point P. What is the angle of refraction as the light enters the fluid at P? Select one: D cross out 2 cross out 90° — ¢ cross out 90° — ¢, cross out 0.0° Cross out ¢ 90° cross out total internal reflection occurs at point P, so the light does not enter cross out the fluid Your answer is correct. Because the light strikes the centre of the hemisphere, it travels along a radius of the sphere to the point P. Any radial path is perpendicular to the surface of the sphere. Therefore the ray of light is normal to the glass-fluid interface at point P. The angle of incidence and angle of refraction are both zero. In other words, the light is not refracted at P. The correct answer is: 0.0° Marks for this submission: 1.00/1.00. Accounting for previous tries, this gives 0.00/1.00. https://eclass.srv.ualberta.ca/mod/quiz/review.php?attempt=6312116&cmid=4375382 3/12

11/16/23, 6:27 PM Question 6 Correct Mark 1.00 out of 1.00 Homework 7: Geometric Optics: Attempt review The diagram shows three layers of transparent media. Light originating inside medium 2 strikes the upper interface (between 1 and 2) and undergoes total internal reflection. The reflected ray strikes the lower interface (between 2 and 3) where the ray is partially reflected and partially refracted. Rank the indices of refraction for the three media (if possible), from smallest to largest. 1 Select one: 5] ns no n na ng n n < N9y < < ng < ng <mn < Ny = ng < ng < ng < Ny <mn < Ny < ng < mn < Ny and ng < ng but we cannot rank nj vs. ng There is insufficient information to rank any of them Your answer is correct. At the upper interface, total internal reflection occurs so we know that n; < ns. At the lower interface, the transmitted ray is refracted away from the normal, so we know that ng3 < na,. cross out cross out Ccross out Cross out cross out cross out cross out Ccross out cross out But how do we rank the indices of refraction for the first and third layers? We know that (1) the angle of reflection equals the angle of incidence, and (2) the two interfaces are parallel surfaces, therefore the two angles of incidence (see diagram below) must be equal. We also know that total internal reflection occurs at the upper interface, so 8; exceeds the critical angle for the upper interface, but not the lower one. Therefore; 2o sin(6;) < n2 ny < ng https://eclass.srv.ualberta.ca/mod/quiz/review.php?attempt=6312116&cmid=4375382 ns ny 6/12

11/16/23, 6:27 PM Homework 7: Geometric Optics: Attempt review Question 9 Correct Mark 1.00 out of 1.00 Drag the correct words into the blanks to complete the following sentence correctly: When an object is placed on the optical axis 20 cm from a convex, spherical mirror which has a focal length of 40 cm it produces a v image which is [ rightway up | ¥ and on the v side of the mirror compared to the object. Note: You only get one attempt at this question because there are only two options for each blank! real inverted Your answer is correct. When the object is placed in front of a convex mirror the image produced is always virtual, right way up and on the opposite side of the mirror to the object. The correct answer is: Drag the correct words into the blanks to complete the following sentence correctly: When an object is placed on the optical axis 20 cm from a convex, spherical mirror which has a focal length of 40 cm it produces a [virtual] image which is [rightway up] and on the [opposite] side of the mirror compared to the object. Note: You only get one attempt at this question because there are only two options for each blank! Marks for this submission: 1.00/1.00. https://eclass.srv.ualberta.ca/mod/quiz/review.php?attempt=6312116&cmid=4375382 9/12