Question

Sam and Samy have taken their math textbooks to the top of a 12 story building and look at the pool which is 116th St. Below them Sam just lets go of his book while Samy throws her book down with an initial velocity of 48 ft./s how many seconds does it take each book to hit the water

Answer 1

Explanation:

Given

height of building h=116 ft

Two textbooks are thrown from building i.e. one is dropped and another is thrown with a velocity of 48 ft/s

for first textbook let
`t_1` be the time required to reach ground

`h=0+(gt_1^2)/(2)`

`116=(32.2* t_1^2)/(2)`

`t_1=\sqrt{(233)/(32.2)}=2.68 s`

For second book

`h=ut+(gt_2^2)/(2)`

`116=48* t_2+(32.2* t_2^2)/(2)`

`32.2t_2^2+96t_2-233=0`

`t_2=(-96\pm √((96)^2+4* 32.2* 233))/(2* 32.2)`

`t_2=1.58 s`