Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
Solve it the standard way once — then learn the shortcut.
Q · Motion in a Straight lineMedium · 45s
A stone dropped from a tower takes 4 s to reach the ground. What is the height of the tower? (Take g = 9.8 m/s²)
TopicMotion in a Straight line
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
← Previous questionQ 30 / 30
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
h = (1/2)gt² = 0.5 × 9.8 × 16 = 78.4 m.
Final Answer: Option C — 78.4 m