Lesson eLearning

A 1.2 metre tall boy stands vertically at 5 pm when the sun’s altitude is 30°. What is the length of his shadow, rounded to two decimal places?

easy 2 marks Class 6 · Science · Light, Shadows and Reflections
Answer
2.08 metres

The correct answer is 2.08 metres — Round to two decimal places: metres.

Step-by-step solution

  1. Draw a right‑angled triangle with the boy’s height as the opposite side and the shadow as the adjacent side.
  2. Recognise that the angle of elevation of the sun is 30°, which is also the angle of the triangle.
  3. Use the relation . So .
  4. Calculate .
  5. Compute metres.
  6. Round to two decimal places: metres.
Common mistake: Using wrong trigonometric ratio or wrong angle

Concept tested: Shadow length using trigonometry

Published · How this solution was prepared and checked

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