A ball falls off of a 3m tall shelf. How long will it take for the ball to hit the ground?
seconds
(hint; x=x0+vot+1/2at?)

0.8s

Explanation:

Given parameters:

Height of shelf  = 3m

Unknown:

Time it will take to hit the ground  = ?

Solution:

To solve this problem, we use the expression below;

         x  = ut + gt²  

x is the height

u is the initial velocity  = 0m/s

g is the acceleration due to gravity  = 9.8m/s²

t is the time taken  = ?

Now insert the parameters and solve for t;

    3  = (0 x t) +( x 9.8 x t²)

    3 = 4.9t²

       t² = 0.6

       t = 0.8s

well clustered together.

points close on a scatter diagram