Notes

This Concept Builder is designed to target student understanding of Archimede's Principle and the concept of buoyancy. Three activities are provided, each of which approaches the topic from a slightly different angle. The opening activity - Paragraph Completion - initiates some thinking about the buoyancy concept as students complete a paragraph with eight missing words or phrases. Students tap on the blanks of the paragraph to toggle through words and phrases to fill in each blank. The cause of the buoyant force and the connection between the amount of buoyant force and the weight of displaced fluid are the primary focus of the paragraph. The second and third activity reference a common classroom demonstration in which an object of known weight is submerged in a full container of water. The displaced water is collected and weighed and its weight is compared to the difference between the actual weight of the object and the apparent weight when submerged in water. Each exercise challenges students to make connections between several quantities - actual weight, apparent weight, buoyant force, weight of displaced fluid, mass and volume of displaced fluid, and the volume of the submerged object.

This Concept Builder consists of 33 different questions that are organized into 9 different Question Groups. The questions and question groups are organized into three different activities. The activities are differentiated as follows:

• Paragraph Completion Question Group 1: Students are provided a paragraph with eight missing words or phrases. They must select the appropriate words and phrases for each blank in order to complete the paragraph.
• Buoyant Force Question Groups 2-5: Students are shown two diagrams. One diagram shows rock hanging from a spring scale above a container of water filled to the rim. The second diagram shows the rock (still on a spring scale) fully submerged in the water and an overflow pan that is on a balance. Students must relate the actual weight, the apparent weight, the amount of diplace water (in L, kg, and N), the buoyant force, and the volume of the rock.
• Which One Doesn't Belong? Question Groups 6-9: Students are presented four statements. Three of them are consistent with one another and the fourth statement is not. They must identify the statement that doesn't belong.

Before using the Concept Builder with classes, we recommend that teachers attempt each of the activities in order to determine which are most appropriate for your classes and what pre-requisite understanding a student must have in order to complete it. Alternatively, the Questions are provided in a separate file for preview purposes (accessible by Task Tracker teachers only).

In order to complete an activity, a student must correctly analyze each question in that activity. If a student's analysis is incorrect, then the student will have to correctly analyze the same or very similar question twice in order to successfully complete the activity. This approach provides the student extra practice on questions for which they exhibited difficulty. As a student progresses through an activity, a system of stars and other indicators are used to indicate progress on the level (displayed for Task Tracker users). A star is an indicator of correctly analyzing the question. Once a star is earned, that question is removed from the queue of questions to be analyzed. Each situation is color-coded with either a yellow or a red box. A red box indicates that the student has incorrectly analyzed the question and will have to correctly analyze it twice before earning a star. A yellow box is an indicator that the question must be correctly analyzed one time in order to earn a star. Once every question in an activity has been analyzed, the student earns a Trophy which is displayed on the Main Menu.

The most valuable (and most overlooked) aspect of this Concept Builder is the Help Me! feature. Each Question Group is accompanied by a Help page that discusses the specifics of the question. This Help feature transforms the activity from a question-answering activity into a concept-building activity. The student who takes the time to use the Help pages can be transformed from a guesser to a learner and from an unsure student to a confident student. The "meat and potatoes" of the Help pages are in the sections titled "How to Think About This Situation:" Students need to be encouraged by teachers to use the Help Me! button and to read this section of the page. A student that takes time to reflect upon how they are answering the question and how an expert would think about the situation can transform their naivete into expertise.

We do not have a lot of resources on the topic of Fluids at The Physics Classroom website. What we do have is listed below. We hope to be adding more in the future.