A body of mass 1 kg has kinetic energy 50 J. Its speed is
- A. 5 m per second
- B. 10 m per second
- C. 50 m per second
- D. 100 m per second
Explanation
From half mv squared equal to 50, v squared is 100 and v is 10 m per second. Forgetting the factor of one half gives about 7.1, and forgetting to take the square root gives 100. Checking the units at the end is a quick guard against both slips.
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