Free Fall: An object is dropped from a bridge. A second object is thrown downwards 1.0 s later. They both reach the water 20 m below at the same instant. What was the initial speed of the second object? Neglect air resistance.
A. 4.9 m/s
B. 15 m/s
C. 9.9 m/s
D. 20 m/s
E. 21 m/s
Answer: B
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