Question

a skydiver falls from rest out of a plane.how long does it take for her to reach a velocity of 250m/s neglecting air resistance.(g=10m/s) :::::please help me

Answer 1

the acceleration is constant, and its velocity is linear

a(t) = 10
v(t) =10t

v(t) = 250 when t=?

Answer 2

Use the formula
\[V _{f} = V _{0} + at\]

You already have the values of the final velocity (250) and the initial velocity (0) and acceleration (10). Just rearrange the formula to get the time :)