a tennis ball is thrown vertically upwards with a speed of v m/s. the height, H metres, reached by the ball is proportional to the square of v. when v = 30m/s, h = 30m work out the value of:
a) H when v = 20m/s
b) v when H = 15 m
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http://web2.0calc.com/questions/please-help_40553
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