Monomath – CBSE | GSEB | IB | JEE Maths by Ajay Yadav (Math King of Katargam) – 15+ Years Experience. Study Notes, Video Lessons, Formula Sheets & PYQs.
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Some Applications of Trigonometry

Previous Year Questions (2022-2024)

📅 Year 2022

  1. A kite flying at height 60 m above ground. String makes 60° with ground. Find string length.
    Show Solution
    sin 60 = 60length => length = 60√3/2 = 120/√3 = 40√3 m
  2. From a point on ground, angle of elevation of building top is 30°. Walking 20 m towards building, angle becomes 60°. Find building height.
    Show Solution
    tan 30 = h/(x+20) => 1/√3 = h/(x+20)\ntan 60 = h/x => √3 = h/x => h = x√3\nSubstitute: 1/√3 = x√3/(x+20) => x+20 = 3x => x=10\nh = 10√3 m

📅 Year 2023

  1. A kite flying at height 60 m above ground. String makes 60° with ground. Find string length.
    Show Solution
    sin 60 = 60length => length = 60√3/2 = 120/√3 = 40√3 m
  2. From a point on ground, angle of elevation of building top is 30°. Walking 20 m towards building, angle becomes 60°. Find building height.
    Show Solution
    tan 30 = h/(x+20) => 1/√3 = h/(x+20)\ntan 60 = h/x => √3 = h/x => h = x√3\nSubstitute: 1/√3 = x√3/(x+20) => x+20 = 3x => x=10\nh = 10√3 m

📅 Year 2024

  1. A kite flying at height 60 m above ground. String makes 60° with ground. Find string length.
    Show Solution
    sin 60 = 60length => length = 60√3/2 = 120/√3 = 40√3 m
  2. From a point on ground, angle of elevation of building top is 30°. Walking 20 m towards building, angle becomes 60°. Find building height.
    Show Solution
    tan 30 = h/(x+20) => 1/√3 = h/(x+20)\ntan 60 = h/x => √3 = h/x => h = x√3\nSubstitute: 1/√3 = x√3/(x+20) => x+20 = 3x => x=10\nh = 10√3 m