Welcome to your Angles of Elevation and Depression(Study by Topics Junior Class) NAME EMAIL PHONE NUMBER 1. The angle of elevation of the top of a tower from a point Q at ground level is 45°. If the tower is 20m high, how far is the bottom of the tower from Q? 30m 20m 40m 10m 5m 2. In a right angled triangle ABC, the sides of the triangle are A < B < C. The hypotenuse of the triangle is B A B² C 3. A 20-foot ladder is leaning against a wall. The foot of the ladder is 7 feet from the base of the wall. What is the approximate measure of the angle the ladder forms with the ground? 19.3° 70.7° 69.5° 20.5° 4. Consider a right angle triangle XYZ, XY = a, YZ = b, XZ = 25.6 and angle of X is 37° then the values of a and b respectively are 15.406, 20.445 18.604, 42.025 19.604, 40.045 17.406, 21.455 5. From the top of a building, a boy is watching a lizard on the ground. If the angle of depression of the lizard is 45° and the lizard is 15m away from the building, how high is the building to the nearest metres? 35m 15m 12m 65m 10m 6. A man stands at the top of a building 40 meters tall. He observers that the angle of elevation of the top of a tower, 50 meters away, is 20 degrees. What is the height of the tower? 58.2 meters 57.1 meters 87 meters 177 meters 7. Two poles of heights 6 m and 11 m stands vertically upright on a plane ground. If the distance between their feet is 12 m, then what is the distance between their tops? 12 m 11 m 14 m 13 m 8. A wheelchair ramp needs to be pitched at 30o. If the ramp is to access a 25-inch step to a door, what will the length of the ramp be? (Round to the nearest inch.) 50 inches 85 inches 86 inches 52 inches 9. The shadow of a tower is 15 m when the sun's elevation is 30^{0}. What is the length of the shadow when the sun's elevation is 60^{0}? 10 m 15 m 5 m 20 m 10. A lighthouse on a cliff, and a sail boat at water level. The height of the light to the base of the cliff is 85m. The sail boat is 110m from the base of the cliff. What is the angle of depression from the light to the boat to the nearest degree? 19 27 15 38 11. A 14 foot ladder is used to scale a 13 foot wall. At what angle of elevation must the ladder be situated in order to reach the top of the wall? 6.89 degrees 21.57 degrees 42.92 degrees 68.4 degrees 12. The string of a kite is 250 m long and it makes an angle of 60^{0} with the horizontal. What is the height of the kite? (Assume there is no slackness in the string) 50√3 150√3 125√3 75√3 13. A tree stands vertically on the ground. From a point on the ground which is 30 m away from the foot of the tree, the angle of elevation of the topmost point of the tree is found to be 45^{0}. What is the height of the tree? 20m 40 m 30 m 10 m 14. From the top of a 20 m high tower, the angle of elevation of the top of a building is 60^{0} and the angle of depression of its foot is 45^{0}. What is the height of the building? 55 m 90 m 120 m 30 m 15. The angle of depression of a spot on the ground, from the top of a wall 10 meters tall, is 70 degrees. How far along the ground, is the spot from the base of the wall? 3.6 meters 27.5 meters 29.2 meters 10.6 meters 16. The angle of elevation of the top of a tree from a point on the level ground is 45°. If the tree is 12m high, calculate the length from the foot of the tree to the point on the level ground where this observation was made. 2.4m 12m 1.2m 6m 36m 17. A man is walking along a straight road. He notices the top of a tower makes an angle of 60^{o} with the ground at the point where he is standing. If the height of the tower is h = 15 m, then what is the distance of the man from the tower? 10.8 meters 6.9 meters 8.67 meters 7.5 meters 18. the diagram below, an aeroplane, P, cruising at an altitude of 10km begins its landing at Changi Airport, denoted by C, at an angle of depression of 10°.Find the horizontal distance between the aeroplane and Changi Airport when the aeroplane begins its landing, correct to 3 significant figures 5.67km 56.7km 9.85km 98.5km 19. Two poles of heights 6 m and 11 m stands vertically upright on a plane ground. If the distance between their feet is 12 m, then what is the distance between their tops? 11 m 13 m 12 m 14 m 20. If the angle of depression of A from B is 42°, what is the angle of elevation of B from A? 48° 42° 138° 84° 132° 1 out of 20 Time is Up! Time's up