Basic Physics queston about falling time, please?

Question

A rock dropped from 1200 ft., ignoring air resistance. How long does it take to hit ground? How fast will it be traveling at impact? Would these answers change if it were thrown 90 mph horizontally? How far would the horizontal rock go before impact?

I have the 32 ft/sec^2. I just don't seem to be doing something correct. I think it hits at the same time. Then I just convert the 90 mph into sec for the first answer.

Thank you for any help. I'm snowed in and can't get to the math lab.

Answer 1

When ignoring frictin, these questions always have the same form:

For vertical motion:
d=1/2*g*t^2

v=g*t
d=1200
g=32

t=sqrt((1200*2)/32)
=8.66 seconds
v=32*sqrt((1200*2)/32)
=277 ft/second

For the second question, you are correct that the rock will strike the ground at the same time.
The difference is that it will have a resultant velocity equal to the sqrt of the sum of the squares of the vertical and horizontal components
=sqrt(277^2+(90*5280/3600)^2)
=306 ft/s
Yes, you convert 90 mph to ft/second and then
vh*t=horizontal distance.
=(90*5280/3600)*8.66
=1,143 ft

j

Answer 2

oh expensive me. i ought to say to positioned in writing the completed technique of what you probably did, and do it again to confirm in case you get any diverse solutions. I trust you; the wording of that "3.80m severe...rock...proper of one million.40 8 m above the floor" is undesirable. attempt to entice a image.. i'm so sorry