A bridge above the river makes an angle of $45^{o}$ with the bank of river. If length of bridge above the river is $150 m$ then breadth of river will be

75 m

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50 \sqrt{2} m

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150 m

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75 \sqrt{2} m

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Solution

The correct option is
B
$75 \sqrt{2} m$

Let $A C$ be the bridge and $A B$ be the width of river.
In $Δ A B C$
$\frac{A B}{A C} = sin 45^{\circ}$
$\frac{A B}{150} = \frac{1}{\sqrt{2}}$
$A B = \frac{150 \sqrt{2}}{2} = 75 \sqrt{2}$
Therefore width of the river is $75 \sqrt{2} m$ .

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A bridge above the river makes an angle of 45o with the bank of river. If length of bridge above the river is 150 m then breadth of river will be

The correct option is B 75√2 mLet AC be the bridge and AB be the width of river.In ΔABCABAC=sin45∘AB150=1√2AB=150√22=75√2Therefore width of the river is 75√2m.

A bridge above the river makes an angle of $45^{o}$ with the bank of river. If length of bridge above the river is $150 m$ then breadth of river will be

The correct option is
B
$75 \sqrt{2} m$

Let $A C$ be the bridge and $A B$ be the width of river.
In $Δ A B C$
$\frac{A B}{A C} = sin 45^{\circ}$
$\frac{A B}{150} = \frac{1}{\sqrt{2}}$
$A B = \frac{150 \sqrt{2}}{2} = 75 \sqrt{2}$
Therefore width of the river is $75 \sqrt{2} m$ .