GRADE-10#HEIGHT AND DISTANCE # TRIGONOMETRY

#HEIGHT AND DISTANCE # TRIGONOMETRY # GRADE 10

 The posts are 120m apart, and the height of one is double of the other. From the middle point of the line joining the feet , an observer found the angle of elevation of their tops to be complementary. Find the height of longer post.

 The angle of elevation of the top of a tower from a point was observed to be (45 degree). On walking 30 m away from that point, it was found to be (30 degree). Find the height of the tower.

  A pole is divided by a point in the ratio of 1:9 from the bottom to top. If the two parts subtend equal angles at 20m away from the foot of the pole, find the height of the pole.

1.       From the top of a cliff the measure of the angle of depression of the top and bottom  of a building are found to be  (45 degree) and 60 degree. If the height of the cliff is 100m. Find the height of the building.

1.       A ladder of 18m reaches a point of 18m below the top of a vertical flagstaff. From the foot of a ladder, the angle of elevation is 60 degree. Find the height of the flagstaff.

1.       The angle of elevation of an aeroplane from a point in the ground is 45 degree. After 15 seconds of flight the angle of elevation changes to 30 degree. If the aeroplane is flying horizontally at a height of 4000m in the same direction, find the speed of aeroplane. [ 192.5 m per  sec square]

The angle of elevation of cloud from a point 10m above the lake is 30 degree and the angle of depression of the reflection of cloud in the lake is 60 degree. Find the height of the cloud.