COMEDK · Physics · 3. Motion In One Dimension
When a body falls in air, the resistance of air depends to a great extent on the shape of the body. Three different shapes are given
Identify the combination of air resistances which truly represents the physical situation. (The cross-sectional areas are the same.)
- A \(I < I I < I I\)
- B II \( < I I I < I\)
- C III \( < \mathrm{II} < \mathrm{I}\)
- D III \( < I < \mathrm{I}\)
Answer & Solution
Correct Answer
(C) III \( < \mathrm{II} < \mathrm{I}\)
Step-by-step Solution
Detailed explanation
The air resistance on an object depends on its area, normal to air flow. Since, area normal to air flow is maximum in case of disc. So, air resistance on it is maximum. The air flow in case of cigar shaped is streamlined, so air resistance is minimum. Hence, the correct order is…
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