Calculate the specific weight and weight of 20dm3 of petrol of specific gravity 0.6.
► Specific weight = Density * Acceleration due to gravity
= 0.6*1000*9.81 = 5886N/m3
► Weight = Volume*Specific Weight
= 5886*0.02 = 117.2N.
If 200m3 of fluid has a weight of 1060N measured on the planet having acceleration due to gravity 6.625m/s2, what will be it’s specific volume?
► Specific Volume is defined as (Volume/Mass of the object) = 1/density
► Mass of object = Weight of object/ acceleration due to gravity = 1060/6.625 = 160 kg
► Density= 160/200 =0.8
► Specific Volume = 1/Density = 1/0.8 = 1.25 m3/kg
For an incompressible fluid does density vary with temperature and pressure?
For an incompressible fluid, the change in density is negligible. Thus it does not change with temperature and pressure.
Specific gravity is what kind of property?
It is independent of quantity of matter present.
If there is bucket full of oil and bucket full of water and you are asked to lift them, which one of the two will require more effort given that volume of buckets remains same?
Density of water is more that oil. Hence, its weight for same volume of oil will also be higher. Therefore, more effort will be required.
If the fluid has specific weight of 10N/m3 for a volume of 100dm3 on a planet which is having acceleration due to gravity 20m/s2 , what will be its specific weight on a planet having acceleration due to gravity 4m/s2?
For same volume, specific weight is directly proportional to acceleration due to gravity.
Specific Weight = 4*10/20 = 2.
Should specific weight of incompressible fluid only be taken at STP?
Therefore, specific weight remains constant.
An instrument with air as fluid was involved in some experiment (specific volume was the characteristic property utilized) which was conducted during day in desert. Due to some reason experiment couldn’t be conducted during day and had to be conducted during night. However there were considerable errors in obtained values. What might be the reason of these errors?
In Desert areas, the temperature at night is considerably lower than at day. Due to this air contracts at night. Hence, its specific volume changes. As specific volume was characteristic property utilized, results obtained showed error due to change in specific volume.
A stone weighed 177 N on earth. It was dropped in to oil of specific gravity 0.8 on a planet whose acceleration due to gravity is 5m/s2. It displaced oil having weight of 100N. What was the volume of oil displaced by the stone?
Volume Displaced = Oil Displaced/(Specific Gravity * Water Density * Acceleration due to gravity) = 100/ (0.8*1000*5).
An compressible fluid’s specific gravity was measured on earth, on a planet having acceleration due to gravity 5.5 times that of earth, and in space at STP. Where will it be having highest value?
Specific gravity is a characteristic property of fluid and is independent of external conditions.