1. CHAPTER 5 Electindo.com PHYSICS FOR JUNIOR HIGH SCHOOL VII

2. Electindo.com PHYSICS FOR JUNIOR HIGH SCHOOL VII SPESIFIC MASS  Specific mass could be different for every object, although the composer particles are the same size. It is because specific mass depends on the total mass and the volume, it has been fixed in international unit conference that the unit of specific mass is kg/m 3. It can be mathematically stated in the following equation : Explanation : ρ = specific mass (kg m -3 ) m = mass (kg) V = volume (m 3 )

3. Electindo.com PHYSICS FOR JUNIOR HIGH SCHOOL VII SPECIFIC MASS The Table of Specific Mass NameSpecific Mass Kg m -3 g cm -3 Air (27°C) Alcohol Wood Ice Water (4°C) Aluminum Zinc Iron Brass Silver Mercury Gold Platinum 1,2 800 300 – 900 920 1.000 2.700 7.140 7.900 8.400 10.500 13.600 19.300 21.450 0,0012 0,80 0,3 – 0,9 0,92 1,00 2,70 7,14 7,90 8,40 10,50 13,60 19,30 21,45

4. Electindo.com FISIKA SMP KELAS VII SPECIFIC MASS  Determining the specific mass of solid a.The regular shape firstly, what we have to do is to measure the mass by using balance or a pair of scales. The volume can be measured using the formula based on its shape, such as cube, bar. The final step is to determine the specific mass by dividing the mass by the volume. b. The irregular shape  To determine the specific mass of liquid the way to identify the specific mass of liquid is to put hydrometer into the liquid.  Specific mass is to determine the kind of substance

5. Electindo.com PHYSICS FOR JUNIOR HIGH SCHOOL VII THE CONCEPT OF SPECIFIC MASS IN REAL LIFE  SUBMARINE when floating, the total specific mass of submarine is lower than the sea’s. when being under water, the total specific mass of submarine is higher than the sea’s. Submarine has some tanks containing water and air.  Gas Balloon gas balloon contains helium. Helium gas has lower specific mass than the air, that is why the balloon can fly up.

6. Electindo.com PHYSICS FOR JUNIOR HIGH SCHOOL VII THE CONCEPT OF SPECIFIC MASS IN REAL LIFE  COLD WATER DRINKING IN THE ICEBOX The pure water can also contain calcium, but we cam not observe by naked-eye. When the water is being cool, the specific mass of water is lower and separated from the calcium that has higher specific mass will come to the bottom and precipated.

7. Electindo.com PHYSICS FOR JUNIOR HIGH SCHOOL VII