## Dependance of "g"

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Dipan
Posts: 158
Joined: Wed Dec 08, 2010 5:36 pm

### Re: Dependance of "g"

@tanvirab....yes brother I know it....but why we use the theory F= mg . that means, g=F/m...
@moon bhai,amarto avro ache...bangla likhte time besi lage je..

tanvirab
Posts: 446
Joined: Tue Dec 07, 2010 2:08 am

### Re: Dependance of "g"

$g =\frac{ F}{m} =$ constant.
The value of $\frac{ F}{m}$ is the same for any object on earth. It does not depend on $m$. Whatever $m$ is, the value of $\frac{ F}{m}$ is the same.

Dipan
Posts: 158
Joined: Wed Dec 08, 2010 5:36 pm

### Re: Dependance of "g"

Thens is not so satisfactory to me......you have written that F/m does not depend on m...look F is a variable..so, if we want to get a constant value of F/m I have to change m with the respect of F...if F/m does not depend on m you can change the value of F without changing the value of m.....but it is not possible......

tanvirab
Posts: 446
Joined: Tue Dec 07, 2010 2:08 am

### Re: Dependance of "g"

Tell me any random value of $m$.

Dipan
Posts: 158
Joined: Wed Dec 08, 2010 5:36 pm

### Re: Dependance of "g"

420 kg..

AntiviruShahriar
Posts: 125
Joined: Mon Dec 13, 2010 12:05 pm
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### Re: Dependance of "g"

hey,m change korle F o change hobee...karon $F$=$\frac{G\cdot m_1 \cdot m_2}{d^2}$......
now let M and m be the mass of earth and that object respectively....
so,$\frac{F}{m}$=$\frac{G \cdot m \cdot M}{m \cdot d^2}$..
\Rightarrow $\frac{F}{m}$=$\frac{G \cdot M}{d^2}$=$g$
\Rightarrow $g$=$\frac{G \cdot M}{d^2}$
so g isn't depending on m

tanvirab
Posts: 446
Joined: Tue Dec 07, 2010 2:08 am

### Re: Dependance of "g"

Ok. $m = 420$ kg. Now what is the value of $g$ for this $m$?

Tanvir

Dipan
Posts: 158
Joined: Wed Dec 08, 2010 5:36 pm

### Re: Dependance of "g"

@Tanvir....of course 9.8......now see g is a constant for a specific place,if I take 420 as the value of m I have to take the value of F 4116.Here no other value of F is acceptable..because g is a constant.What will be the value of F ,it is depends only the value of m....Why I can't use the value of F 123 in here?Because of m....
@Anti...ami ata jani..ssc er physics book e atai ache..kintu amar quedtion hocche F=mg theory nie...

tanvirab
Posts: 446
Joined: Tue Dec 07, 2010 2:08 am

### Re: Dependance of "g"

I don't care what $F$ is. My question was what is $g$? Does it's value depend on the value of $m$? Will the value of $g$ be different if you choose a different $m$?

Dipan
Posts: 158
Joined: Wed Dec 08, 2010 5:36 pm

### Re: Dependance of "g"

yes, from this theory
F=mg
we can say that g depends on m..........