Question

in a certain lake the top of a bud of lotus is 1mt.above the water surface. forced by wind it gradually advanced and was just submerged at a distance of 4mt.find the depth of the lake.​

Answer 1

Answer:

Depth of the lake will be 7.5 metre.

Step-by-step explanation:

In the question it is written that the lotus is 1 metre above the water surface.

And the part which is submerged in water let it be y .

So, the total length will be y+1.

Now, it says that due to wind it gradually advanced to a distance of 4 metre.

To remember the length of the stem will still be same.

We will apply Pythagoras Theorem in this , the reason being that the stem was making a right angle as it is vertical and water being horizontal.

H² = P² + B²

(y+1)² = y² + 4²

y² + 2y + 1 = y² + 16

2y + 1 = 16

2y = 15

y = 7.5 metre

So, the depth of the lake will be 7.5 metre.