Alien paperweight

Question

In a bid to escape from your alien captors you hurl your paperweight straight up towards the door switch on a space ship above you. If the switch is 25m above you how fast does the paperweight need to leave your hand?

Answer 1

Use the equation v² =v₀² - 2as for this problem v will equal 0 at the door switch and so v₀²= 2(9.8)25 and v₀² = 490m²/s² and v₀ = 22.14m/s.