A ball is thrown straight up into the air with a speed of 13 m/s. If the ball has a mass of 0.25 kg, how high does the ball go? Acceleration due to gravity is g=9.8m/s^2
The total energy, i.e. sum of kinetic and potential energy, is constant.
i.e. E = KE + PE
Initially, PE = 0 and KE = 1/2 mv^2
At maximum height, velocity=0, thus, KE = 0 and PE = mgh
Since, total energy is constant (KE converts to PE when the ball is rising),
therefore, KE = PE
or, 1/2 mv^2 = mgh
or, h = v^2 /2g = 13^2 / (2x9.8) = 8.622 m
Hope this helps.
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