Arianna kicks a soccer ball off the ground and in the air with an initial velocity of 42 feet per second. Approximately, how long does it take until the soccer ball hits the ground again?

Question

anonymous · Answer

Arianna kicks a soccer ball off the ground and in the air with an initial velocity of 42 feet per second. Approximately what maximum height does the soccer ball reach?

I think this can not be solve due to lack of data.

anonymous · Answer

lol!

anonymous · Answer

Here's the for choices 
	
a	1.3 secs
b	2.6 secs
c	16.0 secs
d	27.6 secs

anonymous · Answer

some options are available or not

anonymous · Answer

^^^ i put them

anonymous · Answer

kk

lgbasallote · Answer

use the formula to get maximum height first

$$S_2 - S_1 = V_1 t + \frac12 at$$
s2 is the maximum height = not given
s1 is initial height = 0
V1 is the initial velocity = 42
a = -9.8 m/s^2
t = time =not given

lgbasallote · Answer

obviously that wont work ;)

anonymous · Answer

you have to deal with two components of the balls motion 
ie 
vertical and horizontal

lgbasallote · Answer

use another formula
$$V_2 = V_1 + at$$
v2 is final speed which will be 0 because v = 0 at max height
v1 = 42
a = -9.8

now solve this...
$$0 = 42 -9.8t$$
$$9.8t = 42$$
can you solve for t?

anonymous · Answer

No this is for my bro i dont know how to

lgbasallote · Answer

hmm if you look closely..that last step is just algebra...

anonymous · Answer

o ok thanks for the help guys

lgbasallote · Answer

btw...you need to multiply the time you get from that by 2

because the one we got was just the first half

anonymous · Answer

I got 8.6 and thats not one of the answers.