1. If a painter's 24-ft ladder is leaned against a vertical wall to where the top of the ladder rests against it at a height of 21½ ft, find the measure of the angle formed between the ladder and the level ground.

     
  2. The roof of a house is designated as a "5 and 12" pitch, i.e., the ratio of the "rise to the run" (see the illustration below).  What is the measure of the roof's angle of inclination (θ), rounded to the nearest tenth of a degree?
    House/Roof-pitch diagram (exercise 2)

     
  3. Grade is defined as the ratio of the change in elevation (or vertical distance) to the change in horizontal distance.
    Road Grade triangle diagram: (exercise 3)
    1. If a stretch of road has an 8% grade, then at what angle measure is the road rising with respect to the horizontal?  Round the answer to the nearest half degree.
    2. If a car travels along this road for ¾-mi what would be the car's change in elevation over this distance?  Express the answer rounded to the nearest whole number of feet.

     
  4. A helicopter pilot reports to an air traffic controller that he is currently hovering at an altitude of 750 m and is at a (horizontal-ground) distance of 4 km from the airport.  At approximately what angle (of elevation) measure, to the nearest whole degree, should the controller aim his binoculars at a height of 20 m (from the level ground) to spot the aircraft?
    ATC & Helicopter diagram (exercise 4)

     
  5. If you hold a quarter at a distance of 2.5 feet from your eye, find the measure of the angle formed between the top and bottom of the coin with your eye as the vertex.
    Eye & Quarter diagram (exercise #5)
    Exercise 5:  You will need to measure the diameter of a quarter.

     
  6. A 5'10" man is standing 100 yards away from you.  What angle measure represents the angle formed between the top of the person's head, your eye (as the vertex), and the bottom of the man's feet?

     
  7. The sun's radius is approximately 432,300 mi and its distance from the Earth averages about 93 × 106 mi.  Determine, to the nearest hundredth of a degree, the measure of the angle formed between the top and bottom of the sun's disc with your eye being the vertex.

     
  8. The moon's diameter is approximately 2160 mi and its distance from the Earth averages about 238,600 mi.  Determine, to the nearest hundredth of a degree, the measure of the angle formed between the top and bottom of the moon's disc with your eye being the vertex.

     
  9. NASA's space shuttles frequently orbit the Earth at an altitude of about 200 mi.  What would be the maximum distance between two points on the Earth's surface which can be seen simultaneously by astronauts aboard a shuttle?
    Earth-Shuttle diagram

     
  10. Approximately 700 mi above the Earth, a telecommunications satellite circumnavigates the Earth.  What is the maximum range between two points on the Earth which can receive signals from the satellite at any given time?

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