Lab 7: Archimedes’ Principle and Density Objective 1. To understand Archimedes’ Principle. 2. To measure the density of unknown substances by two methods: Archimedes’ Principle and density definition Background When an object is submerged in a fluid, there are two forces that are acting on it. There is gravity which is the weight of the object which is pointed down, and there is the buoyant force which is an upward force. Archimedes’ Principle states that the buoyant force acting on an object submerged in fluid is equal to the weight of the fluid displaced by the object. The equation for this is B = W L = m L g = ρ L V o g, where B is the force of buoyancy. Procedure Part 1: 1. Record the Id of each aluminum cylinder in Table 1. 2. Weigh each cylinder, record these names in Table 1. 3. Fill a beaker with water, then using figure 1 as a guide, suspend a cylinder from the scale and sumberge it into the water. 4. Determine the volume of each aluminum cylinder, record these values in Table 1. 5. measure the apparent weight of the submerged cylinder and record the value in Table 1. 6. Repeat steps 4 and 5 for each of the remaining 2 cylinders. 7. Calculate the force of buoyancy for each cylinder reporting the values in grams in Table 1. 8. Plot B as a function of V o . You should have 3 points. Fit the data with a regression line, and ρ L could be obtained from the slope.
- Spring '17