Angles of Elevation and Depression, Short questions (Question 1 - 3)


Question 1:
Diagram below shows two vertical poles on a horizontal plane. J, K, L, M and N are five points on the poles such that KL = MN.
Name the angle of elevation of point J from point M.

Solution:

Angle of elevation of point J from point M=KMJ


Question 2:
Diagram below shows two vertical poles JM and KL, on a horizontal plane.
The angle of depression of vertex K from vertex J is 42o.
Calculate the angle of elevation of vertex K from M.

Solution:
JN = 10 tan 42o = 9.004 m
NM = 25 – 9.004 = 15.996 m
KL = NM = 15.996 m
tanKML= KL ML                    = 15.996 10                    =1.5996 KML= tan 1 1.5996              = 57 o 59 '


Question 3:
Diagram below shows a vertical pole KMN on a horizontal plane. The angle of elevation of M from L is 20o.
Calculate the height, in m, of the pole.

Solution:
tan 20 o = KM KL 0.3640= KM 15 KM=5.4m Height of the pole = 9+5.4=14.4m