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Question
A pebble is thrown vertically upwards with a speed of 20 m s-1. How high will it be after 2 s? (Take g = 10 m s-2)
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Solution
Initial velocity, u = 20 m/s
Time, t = 2s
g = 10 m/s2
Maximum height reached in 2s, H = (1/2) gt2
Or, H = (1/2) (10) (2) 2
Or, H = 20 m
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