Experiment : To determine the density of solid ( Denser than water ) by using a spring balance and a measuring cylinder.
Apparatus : Metallic block or a cylinder , fine cotton thread , a spring balance measuring cylinder , beaker , water and a clamp stand. In place of metallic cylinder , brass or steel Bob can also be taken.
Theory : Density of a substance is defined as mass of a unit volume of the substance.
Density = mass / Volume
The SI unit of density is kgm-3
Diagram :
Observation :
Least count of spring balance = ........ g
Mass of metallic cylinder using spring balance
(i) m1 = ........ g (ii) m2 = ......... g
Mean mass of the metallic cylinder= m1+m2 / 2 = ......... g
Calculations :
Mean mass of the cylinder , m = .......g
Mean volume of the cylinder , V = ...... cm3
Hence , density of the solid = m/V = ..... g/cm3
Result : The Density of solid = ....... g/cm3
Precautions :
1. The metallic cylinder should be clean and dry.
2. The spring balance should not have any zero error.
3. The thread used for lowering the metallic cylinder in water should be thin.
4. No air bubbles should remain sticking to the cylinder in water should be thin.
5. The eyes should be at the same level as that of the lower meniscus of water , when taking the reading of water level in the cylinder.
6. The cylinder should be wholly dipped in water.
7. When the metallic cylinder is immersed in measuring cylinder, the water should not spill from the measuring cylinder.
8. Always check that the graduations of the measuring cylinder are not faulty.
9. Water should be preferably at 4°C .
10. The metallic cylinder should not touch the sides of measuring cylinder.
Source of Error :
1. The impurities present in water may alter its density.
2. The steel or brass Bob should not be porous.
3. The thread used in the experiment may also absorb some water.