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 5m 20m 10m 40m None 2. In the diagram below, a diver is to retrieve an object that is 14m away from the wall of a swimming pool. It is given that the angle of depression of the object from the pool platform is 30°. Find the vertical distance the diver has to swim in order to retrieve the object, correct to 3 significant figures. 8.08m 24.2m 7.00m 12.1m None 3. 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? 10 m 30 m 40 m 20m None 4. 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 56.7km 5.67km 98.5km 9.85km None 5. In 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 distance CP, correct to 3 significant figures 57.6km 10.2km 5.76km 102km None 6. 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.) 85 inches 52 inches 50 inches 86 inches None 7. In a ΔABC right angled at B, sin A = 1/2, if BC = 6 cm then the value of AC is: 9 cm 3cm 6 cm 12 cm None 8. 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? 13 m 12 m 11 m 14 m None 9. 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 None 10. From the top of a tower of height 75 m, a guard sees two prisoners, both due west of him. If the angles of depression of the two prisoners are 10^{o} and 17^{o}, calculate the distance between them. 210 m 190 m 220 m 180 m 200 m None 11. A tree is 200 ft tall. If a man is standing 75 ft away from the tree, what is the angle of elevation to the bird he is looking at? 25° 56° 69.5° 98° None 12. A photographer points his camera to the top of a building forming an angle of elevation of 50a. If he stands 70 meters from the building, how tall is the building? 83.4 meters 102.5 meters 53.6 meters 45 meters None 13. A 1.8m tall man is walking inside a tunnel. He shines the torchlight on his helmet upward at an angle of 35° to a point Q at the top of the tunnel as shown in the diagram below. Given that the horizontal distance of OP is 7m, what is the height of the tunnel, correct to 3 significant figures? 5.82m 4.90m 6.70m 7.53m None 14. A skier took 56s to traverse down the snowy slopes of a 300m high hill. Using the diagram below, if the skier traversed from point S to point Uand the angle of depression from S to U is 60°, find the speed, in km/h, at which he came down the slopes. Correct the answer to 3 significant figures. 19.4 11.2 22.3 38.7 None 15. A ladder of length 8 m rests against a wall so that the angle between that ladder and the wall is 31°. However far is the base of the ladder form the wall? 6 m 4.1 m 7.1 m 3.6 m 6. 3 m None 16. A lighthouse on a cliff, and a sail boat at water level. The height of the light to the base of the cliff is 80m. The sail boat is 120m from the base of the cliff. What is the angle of elevation from the boat to the light to the nearest degree? (number only) 34 38 43 25 None 17. The angle of elevation of the top of a building from a point 80m away on a level ground is 25°. Calculate the height of the building to the nearest metre. 37m 33m 30m 38m 50m None 18. 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 19.604, 40.045 18.604, 42.025 15.406, 20.445 17.406, 21.455 None 19. 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 None 20. A ladder of length 6 m leans against a vertical wall so that the base of the ladder is 2 m from the wall. Calculate the angle between the ladder and the wall. 31 22.8 20 19.5 18 None 1 out of 20 Time's upTime is Up!