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

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The discussion centers on calculating the specific gravity of a cube weighing 0.54 kg with 5 cm sides. The cube's volume is determined to be 125 cm³, leading to a calculated density of 4.32 g/cm³, which does not match the provided answer choices. There is confusion regarding the terms "specific gravity" and "specific weight," with a consensus that specific gravity should be unitless and typically relative to water. Participants express concern over the validity of the answer choices given the calculations and definitions discussed. Ultimately, the conclusion suggests that the correct specific gravity is indeed 4.32 g/cm³, not aligning with any of the options provided.
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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?
 
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Raven1972 said:
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?
 
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.
 
Borek said:
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...
 
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