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[manal950]

Hi ..

How are you all ...

I have a question .. I tried solved

http://store2.up-00.com/Feb12/0Mf90391.jpg

 

[LawrenceC]

Volume is cubic meters, not square meters which is area.

Specific gravity is the ratio of density of a material to that of water which is 1000kg/cubic meter.

Mass:

M=specific gravity * density of water * volume

 

[manal950]

mass of tank

M=specific gravity * density of water * volume of oil
= (0.8) (1000) (4)
= 3200kg/m^3

mass of waater : M=density of waterX volume X g

Here is the volume of water will be 2
1000 X 2 X 9.81
= 19620kg/m^3Total is (3200kg) + (19620kg) = 22820kg/m^3Is ok now ?

 

[LawrenceC]

mass of tank

M=specific gravity * density of water * volume of oil
= (0.8) (1000) (4)
= 3200kg/m^3

mass of waater : M=density of waterX volume X g

Here is the volume of water will be 2
1000 X 2 X 9.81
= 19620kg/m^3


Total is (3200kg) + (19620kg) = 22820kg/m^3


Is ok now ?

Units work just like ordinary algebra. In your first computation for mass of oil you multiply density in kg/m^3 by m^3 yet get kg/m^3. Question requests mass. You have correct number but wrong units.

In your second computation, why do you multiply by g? Your units will be:

(kg/m^3)*m^3*(m/sec^2) which is kg-m/sec^2 which is Newtons.

Pay attention to units. If your units don't jive with what should be your answer, you obviously have an error.

 

[manal950]

3200 kg , 2000 kg, thus the total is 5200 kg.

what about diagram ?

 

[LawrenceC]

In your diagram which liquid is oil and which is water? The accuracy of the relative amounts of oil and water could be improved. As your diagram now stands, I do not think the teacher is going to give you much credit for it.

 

[manal950]

http://www.roo7oman.com/up/files/384678.jpg

see here

 

[LawrenceC]

Your diagram looks good but if your oil is that dirty, you should change it!

 

[manal950]

hhhhh how is dirty ?

 

[LawrenceC]

I was joking. If the oil in the crankcase of your automobile looks that black, you should change it.

 

[manal950]

hhhhhhhh ...I don't have money to change it . ^)^