An object is dropped from rest from a height. It hits the ground at 20 m·s⁻¹. Ignoring air resistance, from what height was it dropped (take g = 9,8 m·s⁻²)?
Answer and explanation
Correct answer: C.
- Step 1: Use with .
- Step 2: m.
Answer
.
Why not the others: : the factor 2 in the denominator was left out. : the velocity was not squared. : 2 was multiplied instead of used as a divisor.
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