Engineering Fundamentals: An Introduction to Engineering, 4th ed.c

9.3 Density, Specific Volume, and Specific Gravity 235

Specific weightis another way to measure how truly heavy or light a material is for a given

volume. Specific weight is defined as the ratio of theweightof the material by the volume that

it occupies, according to

(9.4)

Again, the weight of something on earth is the force that is exerted on its mass due to gravity.

We will discuss the concept of weight in more detail in Chapter 10. In this chapter, it is left as

an exercise (see Problem 9.4) for you to show the relationship between density and specific

weight:

specific weight (density)(acceleration due to gravity)

The density, specific gravity, and the specific weight of some materials are shown in Table 9.1.

specific weight

weight

volume

TABLE 9.1 Density, Specific Gravity, and Specific Weight of Some Materials

(at room temperature or at the specified temperature)

Specific Weight

Material Density (kg /m

3

) Specific Gravity (N/m

3

)

Aluminum 2740 2.74 26,880

Asphalt 2110 2.11 20,700

Cement 1920 1.92 18,840

Clay 1000 1.00 9810

Fireclay brick 1790@100C 1.79 17,560

Glass (soda lime) 2470 2.47 24,230

Glass (lead) 4280 4.28 41,990

Glass (Pyrex) 2230 2.23 21,880

Iron (cast) 7210 7.21 70,730

Iron (wrought) 7700@100C 7.70 75,540

Paper 930 0.93 9120

Steel ( mild) 7830 7.83 76,810

Steel (stainless 304) 7860 7.86 77,110

Wood (ash) 690 0.69 6770

Wood ( mahogany) 550 0.55 5400

Wood (oak) 750 0.75 7360

Wood (pine) 430 0.43 4220

Fluids

Standard air 1.225 0.0012 12

Gasoline 720 0.72 7060

Glycerin 1260 1.26 12,360

Mercury 13,550 13.55 132,930

SAE 10 W oil 920 0.92 9030

Water 1000@4C 1.0 9810

Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s).

圀圀圀⸀夀䄀娀䐀䄀一倀刀䔀匀匀⸀䌀伀䴀圀圀圀⸀夀䄀娀䐀䄀一倀刀䔀匀匀⸀䌀伀䴀