Learning Science through Forensics Activities
Learning Science Through Forensics Activities
Activity #5: Creating a Field Guide to Blood Spatter, Part I
Objectives: Students will learn about the physical properties of water. Students will apply the basic concepts of experimental design. Students will further develop their graphing skills. Students will develop a tool for use in a follow-up activity.
Time: 60-80 minutes
Introduction: With the blood spatter activities (Part I alone or Part I and II in combination), students will generate a field guide for later use (e.g. during a lab exam or for the analysis of a cold case). Asking students to create a guide that they know they will have to rely on for an upcoming activity often enhances the quality of the outcome. The guide can be developed in the form of: graphs only with descriptive captions. This would require students to use their graphs to interpret new data and reinforces the skill of graphic interpretation. graphs and representative physical samples (i.e. folded newsprints containing the spatter samples or spatter tracings) organized into a file of some sort. an entirely digital guide with graphs and possibly digital photos of spatter patterns generated during these exercises.
Blood is mostly water, therefore the physical properties of water, its cohesion, adhesion, and high surface tension, affect the patterns blood makes when it spatters. This lab activity reinforces some of these important physical properties. It could be conducted as a deductive activity in which students are asked to explain the results of the various experiments in terms of water’s physical properties. It could follow, for example, a lab activity where students compare the properties (drop size, evaporation rate) of three different liquids and then precede, for example, a discussion of the differences in composition and physical properties between blood and water.
This activity as written also reinforces some of the key components of
Activity #5: Creating a Field Guide to Blood Spatter, Part I
Objectives: Students will learn about the physical properties of water. Students will apply the basic concepts of experimental design. Students will further develop their graphing skills. Students will develop a tool for use in a follow-up activity.
Time: 60-80 minutes
Introduction: With the blood spatter activities (Part I alone or Part I and II in combination), students will generate a field guide for later use (e.g. during a lab exam or for the analysis of a cold case). Asking students to create a guide that they know they will have to rely on for an upcoming activity often enhances the quality of the outcome. The guide can be developed in the form of: graphs only with descriptive captions. This would require students to use their graphs to interpret new data and reinforces the skill of graphic interpretation. graphs and representative physical samples (i.e. folded newsprints containing the spatter samples or spatter tracings) organized into a file of some sort. an entirely digital guide with graphs and possibly digital photos of spatter patterns generated during these exercises.
Blood is mostly water, therefore the physical properties of water, its cohesion, adhesion, and high surface tension, affect the patterns blood makes when it spatters. This lab activity reinforces some of these important physical properties. It could be conducted as a deductive activity in which students are asked to explain the results of the various experiments in terms of water’s physical properties. It could follow, for example, a lab activity where students compare the properties (drop size, evaporation rate) of three different liquids and then precede, for example, a discussion of the differences in composition and physical properties between blood and water.
This activity as written also reinforces some of the key components of