Get Answers to all your Questions

header-bg qa

From the top of a tower, 100 m high, a man observes two cars on the opposite sides of the tower and in same straight line with its base, with angles of depression 30^{\circ} and 45^{\circ}. Find the distance between the cars. [Take \sqrt{3}=1.732 ]

 

 

 

 
 
 
 
 

Answers (1)

Let tower AB=100\; m

Car 1 is at point C.

Car 2 is at point D.

\angle ACB=30^{\circ}

\angle ADB=45^{\circ}

To find : length CD

In   \bigtriangleup ABC, \angle ABC=90^{\circ}

\Rightarrow \tan 30=\frac{AB}{BC}

\Rightarrow \frac{1}{\sqrt{3}}=\frac{100}{BC}\; \; \; \; \; \left ( \tan 30=\frac{1}{\sqrt{3}} \right )

\Rightarrow BC=100\sqrt{3}\; m

In  \bigtriangleup ABD, \angle ABD=90^{\circ}

\Rightarrow \tan 45 =\frac{AB}{BD}

\Rightarrow \tan 45 =\frac{1}{BD} \: \: \: \: \: \: \: \left ( \tan 45=1 \right )

\Rightarrow BD=100\: m

CD=BC+BD=100\sqrt{2}+100=100(\sqrt{3}+1)

  =100(1.732+1)=100(2.732)=273.2\; m

Distance between cars is 273.2 metres.

 

Posted by

Ravindra Pindel

View full answer