Question

If there were no air resistance, how long would it take a free-falling skydiver to fall from a plane at 3500 m to an altitude of 400 m , where she will pull her ripcord?

Answer 1

By equation of motion we have S = ut + 0.5 a$t^{2}$

Where u = Initail velocity, S= dispalcement, t = time taken, a = acceleration

Here S = 3500-400 = 3100m, u = 0m/s, g = 9.8 m/$s^{2}$

So, 3100 = 0+0.5*9.8*$t^{2}$

       $t^{2}$ = 3100/4.9

       t = $\sqrt{3100/4.9}$

      t = 25.15 seconds