Archimides Principle

Experiment 12 Archimedes’ Principle

Fig. 12-1 Equipment Triple Beam balance Wood cylinder 2 Metal cylinders String Graduated cylinder Pipette Vernier caliper Rod & Clamp
Overflow containerExperiment 12 Archimedes’ Principle
Advance Reading: Serway & Jewett - Chapter 14, Section 14-4 Objective: The objective of this lab is to measure the buoyant force on a number of objects. Theory:Archimedes’ principle states that a body wholly or partially submerged in a fluid is buoyed up by a force equal in magnitude to the weight of the fluid displaced by the body. It is important to rememberthat fluid includes liquids and gases. This force is given by: FB = ρVg (Eq 1)

where ρ (rho) is the density of the fluid, V is the volume of fluid displaced and g is acceleration due to gravity. Itis the buoyant force that keeps ships afloat in water and hot air balloons floating in air. In this experiment, the buoyant force will be measured three ways and the results compared. The first methodis by the measurement of force. This method involves weighing an object first in air, then in water, and using the difference in weight as the buoyant force. Though the object's mass does not change,its apparent weight will change when measured while immersed in a fluid that is denser than air. The second method is the displaced volume method. The volume of fluid displaced by the object ismeasured and its weight calculated. The weight of the water displaced is equal to the buoyant force exerted on the object, by Archimedes' Principle. The third method is by the buoyant force equationmethod. By measuring the dimensions of the object and calculating the volume, one can determine the buoyant force (by using Εq-1) that would be exerted on the object when it is submerged in a fluid of knowndensity ρ . Please note that for the third method, the volumes of interest are different for objects that float and objects that sink. Procedure

Part 1: Force Measurement method- Weight
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