Friday, January 6, 2017 Your Learning Goal: After students conduct experiments to figure out how much water an object displaces, they will understand that the amount of water displaced is equal to the volume of the object. Table of Contents: Displacement in a Liquid 34R Pre-Write (34L): What measurement do we use when we want to figure out how much space something takes up? Homework: Archimedes Writing Due Today Agenda: 1. Pre-Write 2. Displacement 3. Reflection
Table of Contents Date Assignment Pg # 1/3/17 Floating Puzzles * 29R 1/5/17 Mass & Floating * 30R 1/9/17 Volume & Floating * 31R 1/13/17 Analyzing Data * 32R 1/18/17 Density Challenge * 33R 1/20/17 Displacement in a liquid 34R
1/20/17 Displacement in a Liquid Catalyst: Why can we not measure liquid volume in cm3? 1/20/17 Displacement in a Liquid We can t measure liquid volume with the units cm3 because 34L 34R
Can you think of a time when you dropped an ice cube into a glass of water or soda and had the glass overflow? Maybe you ve filled a sink with water to do the dishes and had it nearly overflowed when you added the dishes. The water that was pushed out of the way when you added the ice cube to your drink or the dishes to the full sink is called displaced water. So how can we tell how much water is displaced?
Time to test displacement Plan carefully How will you measure ACCURATELY how much water an object displaces? Imagine this situation and how you could collect and measure the water that overflows: A tub of water is filled to the brim with water. As soon as any object touches the surface, some water spills over the side. Once the object is in the water and settles down, some amount of water has overflowed. That is displaced water. That is the water you want to measure! How can you measure it? Think about how to carefully collect and accurately measure the overflow, EVEN IF IT IS A TINY AMOUNT. How have you measured the volume of liquids before?
On your worksheet
1/20/17 Displacement of a Liquid The water that is pushed out of the way when you add an object to a container that is completely filled with water is called displaced water. I can measure to allow me to predict how much water will be displaced when an object is fully submerged (completely under) a liquid. The amount of displaced water would be different if the object was only partially submerged (part-way under) in a liquid. The amount of the object or under water would be equal to the amount of water that is. The buoyant force on an object is equal to the weight of the liquid displaced by the object 34R
The displaced water of fully submerged objects tell me the (length/mass/volume) of an object. However, the displaced water of partially submerged objects tell me the (length/mass/volume) of the object (under/ over) the water. I noticed the objects that sank were (fully/ partially) submerged because they had densities (more/less) than, which is the density of water. For example, the copper cube + aluminum cube have a density of. I noticed the objects that floated were (fully/partially) submerged and had densities (more/less) than, which is the density of water. For example, the 2 pine cubes + 2 oak cubes have a density of.
Reflection If we want to find the volume of an irregular object, would we use the displacement method or use the formula (LxWxH)? Explain why. 34L
1/20/17 Displacement in a Liquid Catalyst: What measurement do we use when we want to figure out how much space something takes up? Reflection: If we want to find the volume of an irregular object, would we use the displacement method or use the formula (LxWxH)? Explain why. 34L 1/20/17 Displacement in a Liquid The water that is pushed out of the way when you add an object to a container that is completely filled with water is called displaced water. I can measure to allow me to predict how much water will be displaced when an object is fully submerged (completely under) a liquid. The amount of displaced water would be different if the object was only partially submerged (part-way under) in a liquid. The amount of the object or under water would be equal to the amount of water that is. The buoyant force on an object is equal to the weight of the liquid displaced by the object. 34R