Use this problem statement to answer the following questions: You recently got promoted at work, and you have moved from a cubicle to your own office. However, since the move, you have noticed that you are having more difficulty reading documents on your desk. To investigate, you decide to compare the lighting in your old cubicle and your new office. In the cubicle, the center of your desk was located directly under the center of a luminaire with dimensions 4ft x 1ft (see Figure 1). Your new office, which has no windows, is lit by a single incandescent bulb in the center of the room with no diffuser or reflector (see Figure 2). 8 ft Luminaire (1ft x 4ft) Desk Back Wall 6 ft Filing Cabinet 8 ft Top View Book Chair shelf 8 ft Filing Cabinet Desk 3 ft Door Book shelf Front Wall Ceiling Floor Front View Figure 1: Cubicle layout. The front view is taken from the perspective of the front wall (highlighted red in the top view). The chair was removed from the front view image to improve visibility of the desk. Filing Cabinet Chair Desk 1 ft 10 ft Chair Chair Top View Bookshelf 10 ft 6 ft 3 ft Desk Front View 4.5 ft 16 ft Bulbs 5 ft Chair 16 ft 1 ft Bulb Coffee Table 8 ft Chair Book shelf Back Wall Door Front Wall Book shelf Ceiling Floor Figure 2: Office Layout. The front view is taken from the perspective of the front wall (highlighted red in the top view). Some items were removed from the front view image for clarity and to improve visibility of the desk. Problem 1. You measure the illuminance at the center of the desk in your old cubicle and find it to be 60 f-c. Calculate the equivalent point-source luminous intensity of the luminaire. Assume the point source would be located at the center of the panel. (1) Problem 2. You check the bulb in your office and find that it consumes 100 watts of electrical power and provides 20 lumens for every watt. A) What is the total output of light energy in all directions from the bulb? B) Calculate the illuminance at the center of your desk in your office from the light bulb. (2) Problem 3. Evaluate whether the illuminance on the desk in both A) your office and B) your cubicle is enough for reading small print/prolonged reading. Refer to MIL-STD1472G and cite the relevant table/section to support your answer. (1) Problem 4. You place a document on your desk in your office and want to calculate the contrast of the letters on the documents compared to the white background. You know that the words on the page have a reflectance constant of 0.05 and the white background (the blank spaces on the page) has a reflectance of 0.80. What is the contrast of the words against the background on the document? Provide an interpretation of this contrast value. (1) Problem 5. To improve the lighting in your office, you consider replacing the lightbulb with a brighter one. A) What is the total luminous flux of a lightbulb needed to meet the minimum illumination guidelines from MIL-STD1472G for reading small print/prolonged reading at the center of your office desk? (1) Problem 6. As another alternative, you consider changing the light fixture while keeping the same bulb to improve the lighting. You have two options: a parabolic reflector at the same height as the current light, or a fixture that lowers the bulb two additional feet (and therefore closer to your desk). Which option would increase the illuminance at your desk more (treat each fixture as a point source when calculating the illuminance)? (1)