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مشاهدة النسخة كاملة : a question


physical
29-04-2007, 08:17
HI

Tow objects with identical volumes but different masses are balanced
will the equilibrium be disturbed if the entire system is completely submerged in the water ? explain

kingstars18
29-04-2007, 12:30
BECAUSE

the effect of gravity in the land > the effect of gravity in the water

physical
29-04-2007, 13:00
so the answer is YES and above is the explanition

المتفيزق
30-04-2007, 18:00
let me give you some additional explanation...
since the two objects are identical in volume but differ in mass ... then the balance point will be nearer to the heavier one... ok>>>
now imersing in water will rise in upthrust equals the weight of the water released by the object which is the same ...
this means that the two masses loose some weight ... and then the new weights must be re-balanced.
I'll give you an example...
suppose that the volume is 100 cm3 and m1=300g whereas m2 =700g
suppose that they are balanced on a bar of length 100 cm , this means that the balance point will be calculated as follows:
m1 x1 = m2 (100-x1) which implies:
x1 = 70 cm from the object m1 .....
now imerse them in water...
the first will loose 100g because of upthrust (archimedes) and so will the object m2 because they are identical...
that is we have now M1 = 200g and M2= 600g
now apply the balancing low and have the following:
M1 X1 = M2 (100-X1) which implies:
X1 = 75cm >>>
ohhhhh the balance is changed...
is it ok now?

physical
06-05-2007, 15:15
so, t he answer is YES