v = Vi + a t = 4.92 - 9.81 t
h = 0 + Vi t - 4.9 t^2 so 0.538 = 4.92 t - 4.9 t^2
4.9 t^2 - 4.92 t + 0.538 = 0
solve quadratic for t
then calculate v
Playing jackstone as a kid, you discovered that there is a certain time before the rubber ball falls and you took advantage of this when picking up the stars on the floor. If you threw the ball 4.92m/s up into the air, how fast will it be moving at a height of 53.86cm? How much time has elapsed upon reaching this height?
3 answers
https://www.mathsisfun.com/quadratic-equation-solver.html
roots; time = .125 and .879 seconds
use .125 because .879 is on the way down
so v = 4.92 - 9.81 (.125)
roots; time = .125 and .879 seconds
use .125 because .879 is on the way down
so v = 4.92 - 9.81 (.125)
why did gravity become 4.9?
2 answers