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High Jumping

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Escape from Planet Earth

How fast would you have to throw a ball upwards so that it would never land?


Stage: 5 Challenge Level: Challenge Level:2 Challenge Level:2

If a projectile is fired at an angle of 45° to the horizontal then the initial speed of the projectile and the distance it travels is related by $d = \frac{v^2}{g}$.


Use the conservation of energy in order to find the speed of the stone. The energy stored in a strip which is extended by $\delta x$ is equal $E = \frac{k \delta x^2}{2}$.