Question

2. A ball is dropped from the roof of a building. The ball strikes the ground after 6 s.
a) How tall, in meters, is the building?
Answer:

b) What is the magnitude of the ball’s velocity just before it reaches the ground?
Answer:

Answer 1

'free fall' question so we will use 1 of 3 kinematic equations.
so where are you stuck @dwade

Answer 2

pretty much which equation to use @DemolisionWolf

Answer 3

awh! ok, makes sense
so what I do is figure out what I know already. so like
initial velocity = ?
gravity = ?
time = ?

and once I see what I know, then I see which of the 3 equations usese the things I know.
so fill in the question marks of what we 'know'

Answer 4

alright so i know:
initial velocity = 0 m/s
gravity = 9.8 m/s
time = 6 s

Answer 5

easy enough.
so, here are the equations to pick from
v = v + at
v^2 = v^2 + 2as
s = s + vt + (1/2)at^2

now 's' means distance, so in our case it's height.
so which of those 3 equations do we know all of the variables but s?

Answer 6

v=v+at

Answer 7

I probably worded my question weird asking you... but I was thinking more like this...

see how i 'check marked' the ones we have and how we are looking for s?