A body covers one half of its journey at 40ms-1 and the next half at 50ms-1. Its average velocity is:
Correct answer: A. 44.4 ms-1
- A. 44.4 ms-1
- B. 45 ms-1
- C. 50 ms-1
- D. 40 ms-1
Explanation
To calculate the average velocity when a body travels equal distances at different speeds, use the harmonic mean formula for average velocity: vavg = (2v1v2) / (v1 + v2).Substituting the given values: vavg = (2 × 40 × 50) / (40 + 50) = 4000 / 90 = 44.4 ms-1.This formula accounts for the equal distances traveled at different speeds. Option A is correct because it accurately uses this formula. Option B is incorrect due to a calculation error. Options C and D are simply the velocities for the respective halves of the journey, not the average velocity.
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