What Is the Specific Gravity of a Cube Weighing 0.54kg with 5cm Sides?

[Raven1972]

1. A Cube of lengths 5cm each. The cube weighs .54kg. What is its specific weight?



2. Answers: A)6 g cm3 B)3 g cm3 C) 2.5 g cm3 D) 2 g cm3



3. 5x5x5 = 125cm3 540g/125= 4.32 g cm3 which is none of the above. Could someone verify that I'm correct before I make an idiot of myself when I challenge the question setter?

 

[Raven1972]

1. A Cube of lengths 5cm each. The cube weighs .54kg. What is its specific weight?



2. Answers: A)6 g cm3 B)3 g cm3 C) 2.5 g cm3 D) 2 g cm3



3. 5x5x5 = 125cm3 540g/125= 4.32 g cm3 which is none of the above. Could someone verify that I'm correct before I make an idiot of myself when I challenge the question setter?

I've found out by a process of deduction that the answer is supposed to be 2.5 gcm3.
Is this wrong?

 

[Borek]

Specific gravity or specific weight?

If sg - I would say your approach (giving 4.32) is correct. There are possible problems here, like sg being relative to something, not necessarily water - so it doesn't have to be identical to density.

Answers given are strange, as units don't fit neither sg nor sw. Specific gravity should be unitles, specific weight units are N/m³ (more generally force/volume). g/cm³ is wrong - unless it is so called gram-force (9.8 mN) per cm³.

 

[Raven1972]

Specific gravity or specific weight?

There are possible problems here, like sg being relative to something, not necessarily water

In this case I believe it supposed to be water

Thanks for the answer. It has confirmed my own conclusions...

 

[rwisz]

The specific gravity, also known as relative density, is the ratio of the density of a substance to the density of a reference substance at a specific temperature. It is a unitless quantity and is often used to compare the density of different materials. In the given scenario, the specific gravity of the cube can be calculated by dividing its density (0.54 kg) by the density of the reference substance, which is often water (1 kg/L). This gives a specific gravity of 0.54, which means the cube is slightly less dense than water.

To verify your calculation, we can use the formula specific gravity = density of substance/density of reference substance. In this case, it would be 0.54 kg/L divided by 1 kg/L, which also gives a specific gravity of 0.54.

It is always important to double check calculations to avoid any mistakes. However, in this case, your calculation is correct and you can confidently challenge the question setter if needed.