A ball is thrown vertically upward at 20 m/s (take g = 10 m/s²). The TIME to reach the highest point is:
A1 s
B10 s
C4 s
D2 s
Answer & Solution
Correct answer: D. 2 s
At the highest point, v = 0 (ball momentarily at rest). Using v = u + at with u = 20, a = −g = −10 (deceleration due to gravity): 0 = 20 − 10t → t = 2 s. At any time after this, the ball falls back.
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