AI Mentor

Check Your IQ

Free Expert Demo

Try Test

Courses

Dropper NEET Course Dropper JEE Course Class - 12 NEET Course Class - 12 JEE Course Class - 11 NEET Course Class - 11 JEE Course Class - 10 Foundation NEET Course Class - 10 Foundation JEE Course Class - 10 CBSE Course Class - 9 Foundation NEET Course Class - 9 Foundation JEE Course Class -9 CBSE Course Class - 8 CBSE Course Class - 7 CBSE Course Class - 6 CBSE Course

Offline Centres

The lower window of a house is at a height of $2 m$ above the ground and its upper window is $4 m$ vertically above the lower window. At certain instant, the angles of elevation of a balloon from these windows are observed to be $60 °$ and $30 °$
, respectively, find the height of the balloon above the ground.

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

2 m

4 m

6 m

8 m

answer is D.

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

Given, height of lower window, h1=2m.
Height of upper window, h2=4m.
Angle of elevation of balloon from the lower window,

θ_{1} = 60 °

And angle of elevation of balloon from the upper window,

θ_{2} = 30 °

Consider the figure,
Question Image

Considering

∆ ADE

tan θ = p e r p e n d i c u l a r b a s e tan 30 ° = H x ⇒ x = H tan 30 ° ⇒ x = H 3 ∵ tan 30 ° = 13

Similarly, consider,

∆ AFG,

tan θ = p e r p e n d i c u l a r b a s e ⇒ tan 60 ° = H + 4 x ⇒ x = H + 4 tan 60 ° ⇒ x = H + 4 3 ∵ tan 60 ° = 3

Comparing the value of x,

H 3 = H + 4 3 ⇒ 3 H = H + 4 ⇒ 2 H = 4 ⇒ H = 2

Therefore, the height above the upper window is 2m.
So, the total height from the ground to the balloon is 2+4+6=8m
Therefore, option 4 is correct.

Watch 3-min video & get full concept clarity

courses

No courses found

Result Producing online coaching for JEE/NEET of south India

Largest All India Test Series for JEE/NEET

Best Online Course for IIT JEE

Best Online Course for NEET

Best Online Course for CBSE

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Get Expert Academic Guidance – Connect with a Counselor Today!