a. When a beam of light falls on a smooth and highly polished surface, the angle of
incidence is 40 .
Explain, with the assistance of diagram and relevant laws, the expected light ray and its pathway.
b. Inside a classroom, a light source of 800 cd is placed above a 0.4 m2 meeting table. Assuming that the light source is located at a height of 2 m vertically from the floor and the height of the meeting table is 0.8 m,
(i) Find the value of illuminance, E, on the top of the meeting table;
(ii) Find the luminous flux, F, falls on the top of the meeting table.
(iii) Calculate the vertical distance between the light source and table if the lux level on the meeting table is required to be 500 lux.
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