im studying for exam which is in 2 days and there is something im having trouble with

the formulas

t = 2 Vv
——–
a

Vv= velocity vertical
a=9.8

this is for where a projectile is launched and landed at same level
the velocity is double because the velocity to get up and landing is the same so it makes sense that you multiply velocity by 2…

BUT my question is what is the formula
t= v
—
a
what is this formula for? to find the average time? instantaneous time? please explain clearly.

If you have constant acceleration you can use the kinematic eqn v = v0 + a*t..

If the initial velocity v0 = 0 then v = a*t

So t = v/a This is the time an object takes to obtain a velocity of v under constant acceleration a