A ball is dropped from 1.8 m and falls freely (g = 9.81 m/s2). What is its speed just before it lands?
Answer and explanation
Correct answer: C. 5.9 m/s
- Step 1: Energy conservation: . Step 2. m/s. Answer: 5.9 m/s. Why not the others: 35 m/s is without the square root; 4.2 m/s forgets the factor of 2 in ; 18 m/s is .
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