A boy whose eye level is 1.3cm from the ground , spots a balloon moving with wind in a horizontal level at some height from the ground . The angle of elevation of the balloon from the eyes of the boy at any instant is 60 degree . After 2 seconds ,the angle of elevation reduces to 30 degrees . If the speed of the wind at the moment is 29root 3 m/s,then find the height of the balloon from ground?
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Let, height of balloon be h,
And the ground distance perpendicular to the balloon be x
tan60= h/x
x=h/root 3
since, distance=speed*time
Therefore, d=29root3*2
d=58root3
tan30=h/(x+58root3)
x+58root3 =h*root3
h/root 3+58 root 3=h*root3
(h+174)/root3=h*root3
2h=174
Height=87m
Total height=87+0.013
=87. 013m=8701.3cm
And the ground distance perpendicular to the balloon be x
tan60= h/x
x=h/root 3
since, distance=speed*time
Therefore, d=29root3*2
d=58root3
tan30=h/(x+58root3)
x+58root3 =h*root3
h/root 3+58 root 3=h*root3
(h+174)/root3=h*root3
2h=174
Height=87m
Total height=87+0.013
=87. 013m=8701.3cm
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