Physics / Math question - GoFuckYourself.com

winter · 09-04-2003, 02:47 PM

At time = 0 a stone is dropped from the top of a cliff above a lake.

Another stone is thrown downward 1.6 seconds later from the same point with an inital speed of 32 m/s.

Both stones hit the water at the same instant. Find the height of the cliff.

Tala · 09-04-2003, 02:49 PM

E=MC2

Dusen · 09-04-2003, 02:50 PM

Remember that the ONLY difference between the two rocks is the initial velocity. one has VI'=0 and other is VI''=32

Accelleration is the same, mass is the same (I assume), distance is the same.

Fabuleux · 09-04-2003, 02:51 PM

51.2m

(edit: first guess, but wrong)

candyflip · 09-04-2003, 02:52 PM

Google it. Google's supposedly got some kickass calculation software hooked into their engine.

Dildozer · 09-04-2003, 02:52 PM

damn i don't remember the old formulas for that, it should be easy if you know them

gornyhuy · 09-04-2003, 02:52 PM

first do distance = distance
left side of equation is 1/2 g (t-1.6)^2 + 32(t-1.6)
right side is 1/2 g t^2

solve for t

then plug in that value of t to either side to find the value of height

Thats pretty close... not bad for in my head anyway.

StuartD · 09-04-2003, 02:53 PM

into a lake? No way to know... since a lake could be at any level above or below sea level, thus effecting the gravitational pull... altering the speed of the falling rock.

Now... had you said ocean....

BV · 09-04-2003, 02:55 PM

not enough info

Fabuleux · 09-04-2003, 02:55 PM

Is it on earth?

winter · 09-04-2003, 02:58 PM

the answer is 27.6 meteres.... I just dont know the equations to use :P

BV · 09-04-2003, 02:58 PM

Quote:

Originally posted by MaskedMan
into a lake? No way to know... since a lake could be at any level above or below sea level, thus effecting the gravitational pull... altering the speed of the falling rock.

Now... had you said ocean....

acceleration rate of gravity is 32 fps square over an ocean, lake, or dry land (not taking wind resistance into account)

winter · 09-04-2003, 03:01 PM

Quote:

Originally posted by gornyhuy
first do distance = distance
left side of equation is 1/2 g (t-1.6)^2 + 32(t-1.6)
right side is 1/2 g t^2

solve for t

then plug in that value of t to either side to find the value of height

Thats pretty close... not bad for in my head anyway.

yeah, you got it, thanks man!

Dusen · 09-04-2003, 03:01 PM

Quote:

Originally posted by BV

acceleration rate of gravity is 32 fps square over an ocean, lake, or dry land (not taking wind resistance into account)

Do they actually teach physics in the USA in imperial units?

That seems very very backward.

Phoenix · 09-04-2003, 03:01 PM

84 metres?

gornyhuy · 09-04-2003, 03:03 PM

Quote:

Originally posted by winter

yeah, you got it, thanks man!

WOOO HOOOO.

Cool... Good to know that shit is still in my brain somewhere even though I never use it anymore.

gornyhuy · 09-04-2003, 03:03 PM

Quote:

Originally posted by Dusen

Do they actually teach physics in the USA in imperial units?

That seems very very backward.

No its always metric from grade school through grad school... at least it was for me.

FATPad · 09-04-2003, 03:03 PM

After careful consideration of all the data, I will say 3.

BV · 09-04-2003, 03:03 PM

Quote:

Originally posted by Dusen

Do they actually teach physics in the USA in imperial units?

That seems very very backward.

I don't know about now but back in 1983 they did.

loverboy · 09-04-2003, 03:05 PM

damn, 3 seconds late. i just forgot the formula.

Dusen · 09-04-2003, 03:09 PM

Touche.

09-04-2003, 02:47 PM	#1
winter Confirmed User Industry Role: Join Date: May 2001 Posts: 570	Physics / Math question At time = 0 a stone is dropped from the top of a cliff above a lake. Another stone is thrown downward 1.6 seconds later from the same point with an inital speed of 32 m/s. Both stones hit the water at the same instant. Find the height of the cliff.

09-04-2003, 02:49 PM	#2
Tala Fucked if I know Join Date: Dec 2002 Location: Do you have a flag? Posts: 23,368	E=MC2 __________________ ICQ: 11120676 \| Google: mindcrime \| Skype: suitemindcrime\|E-Mail: mindcrime AT gmail.com\|PR girl with great writing skills for hire!!!! Contact me to work for YOU!\|TECHIEMEDIA? 24/7 support from some of the best techs in the biz. Tell Jim that I sent you.

09-04-2003, 02:50 PM	#3
Dusen Confirmed User Join Date: Aug 2002 Location: East Coast. Posts: 2,251	Remember that the ONLY difference between the two rocks is the initial velocity. one has VI'=0 and other is VI''=32 Accelleration is the same, mass is the same (I assume), distance is the same. __________________ Penis Pill Sponsor List and Reviews: http://www.pillsponsors.com

09-04-2003, 02:51 PM	#4
Fabuleux Confirmed User Join Date: May 2003 Location: The Netherlands Posts: 2,543	51.2m (edit: first guess, but wrong) __________________

09-04-2003, 02:52 PM	#5
candyflip Carpe Visio Industry Role: Join Date: Jul 2002 Location: New York Posts: 43,065	Google it. Google's supposedly got some kickass calculation software hooked into their engine. __________________ Spend you some brain. Email Me

09-04-2003, 02:52 PM	#6
Dildozer Confirmed User Join Date: Jul 2002 Location: Montreal Posts: 7,519	damn i don't remember the old formulas for that, it should be easy if you know them __________________ Spam link here

09-04-2003, 02:52 PM	#7
gornyhuy Chafed. Join Date: May 2002 Location: Face Down in Pussy Posts: 18,041	first do distance = distance left side of equation is 1/2 g (t-1.6)^2 + 32(t-1.6) right side is 1/2 g t^2 solve for t then plug in that value of t to either side to find the value of height Thats pretty close... not bad for in my head anyway. __________________ icq:159548293

09-04-2003, 02:53 PM	#8
StuartD Sofa King Band Join Date: Jul 2002 Location: Outside the box Posts: 29,903	into a lake? No way to know... since a lake could be at any level above or below sea level, thus effecting the gravitational pull... altering the speed of the falling rock. Now... had you said ocean.... __________________ This is me on facebook This is me on twitter

09-04-2003, 02:55 PM	#9
BV wtf Industry Role: Join Date: Sep 2001 Location: Bikini State, FL USA Posts: 10,914	not enough info

09-04-2003, 02:55 PM	#10
Fabuleux Confirmed User Join Date: May 2003 Location: The Netherlands Posts: 2,543	Is it on earth? __________________

09-04-2003, 02:58 PM	#11
winter Confirmed User Industry Role: Join Date: May 2001 Posts: 570	the answer is 27.6 meteres.... I just dont know the equations to use :P

09-04-2003, 03:01 PM	#15
Phoenix BACON BACON BACON Industry Role: Join Date: Nov 2002 Location: Poems everybody, the laddie fancies himself a poet Posts: 35,469	84 metres? __________________ Skype Phoenixskype1 Telegram PhoenixBrad https://quantads.io

09-04-2003, 03:03 PM	#18
FATPad Confirmed User Join Date: Oct 2001 Posts: 6,693	After careful consideration of all the data, I will say 3. __________________ <a href="http://www.adultcontent.co.uk">Adult Content UK - Great British Content</a>

09-04-2003, 03:05 PM	#20
loverboy When it rains, it pours Industry Role: Join Date: May 2003 Posts: 20,609	damn, 3 seconds late. i just forgot the formula.

09-04-2003, 03:09 PM	#21
Dusen Confirmed User Join Date: Aug 2002 Location: East Coast. Posts: 2,251	Touche. __________________ Penis Pill Sponsor List and Reviews: http://www.pillsponsors.com