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Carnivean
Sep17-06, 03:22 PM
Ok:

Note: Acceleration due to gravity: g = 9.8 m/s

A feather is dropped inside a vacuum chamber.

A) What is the Velocity after 0.30 sec?

B) How far has it fallen after 0.30 sec?

I'm stuck on this.. it seems simple.. but maybe too simple. I think there is more too it. Any help?

Hootenanny
Sep17-06, 03:24 PM
Welcome to the Forums,

According the the policy one is supposed to show ones efforts before asking for assistance.

Carnivean
Sep17-06, 03:26 PM
Umm.. I said I was stuck. I do not know where to begin at? Help me?

Hootenanny
Sep17-06, 03:30 PM
Acceleration is the rate of change of velocity with respect to time. Now, if an object is accelerating at 9.8 m/s/s (note the units) how fast will it be going after 1 second? 0.3 seconds?

Carnivean
Sep17-06, 03:32 PM
after 1 sec it will go 9.8 right? and after .3 sec it will go 2.94.. i think.

Hootenanny
Sep17-06, 03:33 PM
after 1 sec it will go 9.8 right? and after .3 sec it will go 2.94.. i think.
Sounds good to me. Now, for the second question what kinematic equations do you know?

Carnivean
Sep17-06, 03:38 PM
for distance I have d = 1/2at (the 't' is squared , but I don't know how to type a small '2' next to it.. if you could show me that too please) this is an equation for the problems where acceleration info is already is included.

where initial velocity is included: d= InitialVelocity x (t) + 1/2a x (t squared)

Hootenanny
Sep17-06, 03:40 PM
for distance I have d = 1/2at (the 't' is squared , but I don't know how to type a small '2' next to it.. if you could show me that too please) this is an equation for the problems where acceleration info is already is included.

where initial velocity is included: d= InitialVelocity x (t) + 1/2a x (t squared)
Your first equation looks applicable here :smile:. To type superscript text simply enclose the text in [#sup#] [#/sup#] tags (without the #).

Carnivean
Sep17-06, 03:43 PM
ok I got .441 meters for the distance which I think sounds right. Almost a half a meter. But could you give me an example of how to do the superscript thing again? Is it [/then the number]? or [#the number#] ? Just show me an example of how you would type it.

Hootenanny
Sep17-06, 03:48 PM
ok I got .441 meters for the distance which I think sounds right. Almost a half a meter. But could you give me an example of how to do the superscript thing again? Is it [/then the number]? or [#the number#] ? Just show me an example of how you would type it.

For example if you wanted to type x2, you would type:
x[#sup]2[/sup#]
Or for subscript;
x[#sub]2[/sub#]
Again, without the # marks.

Carnivean
Sep17-06, 03:53 PM
ok thanks soo much for your help.. you don't know how much it is appreciated. I will be back many a times probably until about january.

let me try - x 2