Support structure for triple beam balance for weighing hanging objects
The story is told that the Greek mathematician Archimedes liked to lounge around in his bath all day. He would work out his geometric proofs on his stomach (he was quite fat) writing with bath oil. One day when he was contemplating why things floated, the idea, which has become known as Archimedes' Principle, occurred to him. He became so excited by his discovery that he jumped out of his bath and ran through the streets of his town shouting "Eureka" which is Greek for "I've found it". In this lab we will attempt to grasp some of Archimedes' excitement by rediscovering his principle.
Part 1 Discovery Activity
a) Put both 20 gram masses in the 2oz cup. Fill the spill-cup as shown by your instructor. Measure the overflow when the cup is softly placed into the spill-cup.
Water displaced by floating cup with masses inside it: ____________mL.
b) Re-fill the spill-cup as before. Prepare to measure overflow. Next, gently float the empty 2oz cup and then gently drop both 20 gram masses directly into the water.
Water displaced by sunk masses and the floating cup: ____________mL.
Weigh each of your objects in air and record in Column M1.
Weigh each of your objects while completely submerged in water and record in Column M2.
Fill the spill cup with water. Slowly lower the first object into the water, collecting the overflow in the cylinder. Record the displaced mass in Column B noting that *1mL of water has a mass of 1 gram. Repeat for all objects.
Mass in Air
M1 – M2
Mass of Displaced Water*
Calculate the density of each object in grams/cm3 , by dividing the mass in air by the volume of displaced water (note that 1mL = 1cm3).
1. A boat is floating in water. What will cause the water level to rise more?
a) A chunk of metal is put in the boat.
b) The same chunk of metal is thrown into the water.
2. A block of steel is suspended in water by a string. What forces act on the block?