When the angle of elevation of the sun increases from 300 to 600 the shadow of a post is diminished by 5 Metres then height of the post is in Metres?

If the ratio of the height of a tower and the length of its shadow is `sqrt3:1`, what is the angle of elevation of the Sun?

Let C be the angle of elevation of sun is θ. 

When the angle of elevation of the sun increases from 300 to 600 the shadow of a post is diminished by 5 Metres then height of the post is in Metres?

Given that: Height of tower is `sqrt3` meters and length of shadow is 1.

Here we have to find angle of elevation of sun.

In a triangle ABC, 

`⇒ tanθ =(AB)/(BC)` 

`⇒ tan θ=sqrt3/1`        ` [∵ tan 60°=sqrt3]`

`⇒ tan θ=sqrt3`

`⇒ θ=60 °`

Hence the angle of elevation of sun is 60°.

Concept: Heights and Distances

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Solution:

In the figure

AB is the tower

BD and BC are the shadow of the tower in two situations

Consider BD = x m and AB = h m

When the angle of elevation of the sun increases from 300 to 600 the shadow of a post is diminished by 5 Metres then height of the post is in Metres?
When the angle of elevation of the sun increases from 300 to 600 the shadow of a post is diminished by 5 Metres then height of the post is in Metres?

In triangle ABD

tan 450 = h/x

So we get

1 = h/x

h = x ….. (1)

In triangle ABC

tan 300 = h/(x + 10)

So we get

1/√3 = h/(x + 10)

Using equation (1)

h√3 = h + 10

h (√3 – 1) = 10

We know that

h = 10/(√3 – 1)

It can be written as

h = [10 (√3 + 1)]/ [(√3 – 1) (√3 + 1)]

By further calculation

h = (10√3 + 1)/ 2

So we get

h = 5 (1.73 + 1)

h = 5 × 2.73

h = 13.65 m

Therefore, the height of the tower is 13.65 m.

Guys, does anyone know the answer?

get from the top of a multi-storeyed building, 90m high, the angles of depression of the top and the bottom of a tower are observed to be 300 and 600 respectively. find the height of the tower? from screen.

From the top of a tower, the angle of depression of the top and bottom of a multistoreyed building are 30 ^o and 60 ^o respectively. If the height of the building is 100m. Find the height of a tower.

Click here👆to get an answer to your question ✍️ From the top of a tower, the angle of depression of the top and bottom of a multistoreyed building are 30 ^o and 60 ^o respectively. If the height of the building is 100m. Find the height of a tower.

When the angle of elevation of the sun increases from 300 to 600 the shadow of a post is diminished by 5 Metres then height of the post is in Metres?

From the top of a tower, the angle of depression of the top and bottom of a multistoreyed building are 30

Question o and 60 o

respectively. If the height of the building is 100m. Find the height of a tower.

Let AC=h be the height of the tower.

Medium Open in App Solution Verified by Toppr

and ED be the multi-storeyed building, where ED=100m

So, ED=BC=100m So, AB=(h−100)m In ΔABE, tan30 o = EB AB ​ ⇒ 3 ​ 1 ​ = EB h−100 ​ ⇒EB= 3 ​

(h−100)       .... (i)

So, DC=EB= 3 ​ (h−100) In ΔADC, tan60 o = DC AC ​ = 3 ​ = 3 ​ (h−100) h ​ ⇒3(h−100)=h ⇒3h−300=h ⇒2h=300 ⇒h=150 metres

Thus, the height of the tower is 150 m.

When the angle of elevation of the sun increases from 300 to 600 the shadow of a post is diminished by 5 Metres then height of the post is in Metres?

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When the angle of elevation of the sun increases from 300 to 600 the shadow of a post is diminished by 5 Metres then height of the post is in Metres?

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[Solved] From the top of a cliff 90 m high, the angle of depression o

Given: As shown in the above figure, AB = 90 m, AB is the given cliff DC is the tower on which the angle of depression is given. The angle of depression of

When the angle of elevation of the sun increases from 300 to 600 the shadow of a post is diminished by 5 Metres then height of the post is in Metres?

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From the top of a cliff 90 m high, the angle of depression of the top and bottom of a tower are 30∘ and 60∘ respectively, then the height of the tower is -

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RSMSSB LDC Official Paper 1 (Held on : 16 Sept 2018)

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30 m 30√3 m (90 - 30√3) m 60 m

Answer (Detailed Solution Below)

Option 4 : 60 m

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RSMSSB LDC Official Paper 1 (Held on : 12 Aug 2018)

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Detailed Solution

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Given:

As shown in the above figure, AB = 90 m,

AB is the given cliff

DC is the tower on which the angle of depression is given.

The angle of depression of the top and bottom of the tower is 30° and 60°.

Calculation:

When the angle of elevation of the sun increases from 300 to 600 the shadow of a post is diminished by 5 Metres then height of the post is in Metres?

Consider the triangle Δ ABC,

⇒ Tan60° = √3/1 = AB/ BC

⇒ BC = 90/√3 = 30×√3 m      ----(1)

Consider the triangle Δ ADE,

⇒ Tan30° = 1/√3 = AE/DE (As DE = BC)

⇒ AE = 30 m      ----(2)

Now, DC = AB – AE

⇒ DC = 90 – 30 = 60 m

∴ DC is 60 m

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