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9. The angle of elevation of the top of an unfinished tower at a distance of75 m from its base is 30°. How much higher must the tower be raisedso that the angle of elevation of its top at the same point maybe 60°?[Take 3 = 1.732.]on the ton​

Answer»

Answer:

31.8 M (APPROX)

Step-by-step EXPLANATION:

Cos 30 = B/H

\frac{ \sqrt{3} }{2}  =  \frac{b}{h}

hypotenuse =  \frac{75 \times 2}{ \sqrt{3} }

h = 150/1.732

Sin30 = p/h

\frac{1}{2}  = p   \div  \frac{150}{1.732}

\frac{1}{2}  =   \frac{p \times 1.732}{150}

1 = p × 1.732x 2 /150

1 = p × 3.464/150

p = 150/3.464

Now,

p= 43.2(approx)

Let x HEIGHT is increased.

So,

Sin 60 =

\frac{p + x}{h}

\frac{ \sqrt{3} }{2}  =  (p + x) \div  \frac{150}{1.732}

\frac{ \sqrt{3} }{2}  =  \frac{(p + x) \times 1.732}{150}

√3 and 1.732 will GET cancelled out.

1/2 = (p+x)/150

150/2 = p+x

75 = p+x

75-43.2= x

75 - 43.2 = x

x = 31.8 m

HOPE IT HELPS



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