Triangles And Properties Of Triangle Question 43
Question: From an aeroplane above a straight road the angle of depression of two positions at a distance 20 m apart on the road are observed to be $ 30{}^\circ $ and $ 45{}^\circ $ . The height of the aeroplane above the ground is:
Options:
A) $ 10\sqrt{3},m $
B) $ 10(\sqrt{3}-1)m $
C) $ 10(\sqrt{3}+1)m $
D) 20 m
Show Answer
Answer:
Correct Answer: C
Solution:
[c] In $ \Delta ABC,\tan 45{}^\circ =\frac{AB}{BC}=\frac{h}{x};1=\frac{h}{x} $ $ h=x $ (i) In $ \Delta ABD, $ $ \tan 30{}^\circ =\frac{AB}{BD}; $ $ \frac{1}{\sqrt{3}}=\frac{h}{x+20} $ $ x+20=\sqrt{3}h; $ $ h+20=\sqrt{3}h $ $ 20=( \sqrt{3}-1 )h; $ $ h=\frac{20}{\sqrt{3}-1} $ $ =\frac{20}{\sqrt{3}-1}\times \frac{\sqrt{3}+1}{\sqrt{3}+1} $ $ =\frac{20(\sqrt{3}+1)}{2}=10(\sqrt{3}+1)m $ Hence the height is $ 10(\sqrt{3}+1)m $ warning Report Error Previous Next Contact info@studyadda.com JEE Main Videos Ncert Solutions Question Bank Study Packages Notes Sample Papers Online Test Solved Papers NEET Videos Ncert Solutions Question Bank Study Packages Notes Sample Papers Online Test Solved Papers 12th Videos Ncert Solutions Question Bank Study Packages Notes Sample Papers Online Test Solved Papers 11th Videos Ncert Solutions Question Bank Study Packages Notes Sample Papers Online Test 10th Videos Ncert Solutions Question Bank Study Packages Notes Sample Papers Online Test Solved Papers 9th Videos Ncert Solutions Question Bank Study Packages Notes Sample Papers Online Test 8th Videos Ncert Solutions Question Bank Study Packages Notes Sample Papers Online Test 7th Videos Ncert Solutions Question Bank Notes Study Packages Sample Papers Online Test 6th Videos Ncert Solutions Question Bank Notes Study Packages Sample Papers Online Test 5th Videos Question Bank Notes Study Packages Sample Papers Online Test 4th Videos Question Bank Notes Study Packages Sample Papers Online Test 3rd Videos Question Bank Notes Study Packages Sample Papers Online Test 2nd Videos Question Bank Notes Study Packages Sample Papers Online Test 1st Videos Question Bank Notes Study Packages Sample Papers Online Test Railways Videos Sample Papers Study Packages Notes Question Bank Online Test Solved Papers UPSC Videos Sample Papers Study Packages Notes Question Bank Online Test Solved Papers SSC Videos Sample Papers Study Packages Notes Question Bank Online Test Solved Papers Banking Videos Sample Papers Study Packages Notes Question Bank Online Test Solved Papers MP State Exams Videos Sample Papers Study Packages Question Bank Online Test Solved Papers Clat Videos Sample Papers Online Test Study Packages Solved Papers Teaching Videos Sample Papers Study Packages Notes Question Bank UP State Exams Videos Sample Papers Study Packages Question Bank Online Test Rajasthan State Exams Videos Sample Papers Study Packages Question Bank Online Test Jharkhand State Exams Videos Sample Papers Study Packages Question Bank Online Test Chhattisgarh State Exams Videos Sample Papers Study Packages Question Bank Online Test Bihar State Exams Videos Sample Papers Study Packages Question Bank Online Test Haryana State Exams Videos Sample Papers Study Packages Question Bank Online Test Gujarat State Exams Videos Sample Papers Study Packages Question Bank Online Test MH State Exams Videos Sample Papers Study Packages Question Bank Online Test Himachal State Exams Videos Sample Papers Study Packages Question Bank Online Test Delhi State Exams Videos Sample Papers Study Packages Question Bank Online Test Uttarakhand State Exams Videos Sample Papers Study Packages Question Bank Online Test Punjab State Exams Videos Sample Papers Study Packages Question Bank Online Test J&K State Exams Videos Sample Papers Study Packages Question Bank Online Test Defence Videos Sample Papers Study Packages Question Bank Online Test NTSE Videos Sample Papers Study Packages Online Test KVPY Sample Papers Study Packages Online Test Pre-Primary Videos Copyright © 2007-2020 | https://www.studyadda.com | Videos | Study Packages | Test Series | Ncert Solutions | Sample Papers | Questions Bank | Notes | Solved Papers | Current Affairs | Articles | Amazing Facts | Free Videos Contact Us | Jobs | About | Media | Notification | Why Studyadda? | FAQ | Lalit Sardana Sir | Purchase Courses | Franchise | Privacy Policy | Refund Policy
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