There is an iron ball with a mass of 32 grams and a volume of 8 cubic centimeters. Is it solid? (the density of iron is 7.8 grams per cubic centimeter.)

There is an iron ball with a mass of 32 grams and a volume of 8 cubic centimeters. Is it solid? (the density of iron is 7.8 grams per cubic centimeter.)

If it is solid, the mass is 8 × 7.8 = 62.4g ≠ 32g, so it is hollow

An iron ball with a volume of 30 cubic centimeters has a mass of 78 grams. The known density of iron is 7.8 grams per cubic centimeter. If the total mass of the ball is 98 grams after the hollow part is filled with some object, what kind of material is it?

The true volume of 78 grams of iron is 10 cubic centimeters. Now the ball is 30, so the extra 20 is hollow
The volume of the injected material is equal to that of the hollow part = 20 cubic centimeters
Mass of injected material = 20 g
Therefore, we can get the density of the injected material = 1g / cm & # 179;
The common density is the density of material water
The answer is: water
Hope to help the landlord

The spring scale hanging density is 7.0 * 10 ^ 3kg / m3. When the metal block is immersed in water, the spring scale shows 29.4n?

Let the volume of the metal block be v
7000*10*v-1000*10*v=29.4
60000v=29.4
v=0.00049
Gravity = 0.00049 * 7000 * 10 = 34.3n