Free Fall
A stone is dropped from the top of a tower 80 m high. How long will it take to reach the ground? (g = 10 m/s²)
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About This Question
- Subject
- physics
- Chapter
- kinematics
- Topic
- free fall
- Difficulty
- Easy
- Year
- 2025
Solution
Correct Answer:
4 s
- Motion Characteristics: Free fall from rest implies u=0 and acceleration g=10 m/s2.
- Equation: h=21gt2.
- Calculation:
- 80=21×10×t2.
- 80=5t2.
- t2=16.
- Result: t=4 seconds.
This easy difficulty physics question is from the chapter kinematics, covering the topic of free fall. It appeared in the 2025 exam.
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