Blood Spatter Analysis Techniques

This video tutorial guides students through a blood spatter impact angle analysis lab. It begins with an introduction to the materials needed, including a protractor, masking tape, a metric ruler, simulated blood, index cards, and a whiteboard. The tutorial then explains how to set up the lab, calculate the desired impact angle, and conduct the experiment by dropping simulated blood at specific angles. Students are instructed to measure the height and width of the blood drops, record the data, and calculate the ratio and actual angle of impact using trigonometry. Finally, students complete the lab by answering analysis questions.

What materials are required for the blood spatter impact angle analysis lab?

• A protractor, masking tape, metric ruler, simulated blood, index cards, and a whiteboard

• A compass, masking tape, metric ruler, real blood, index cards, and a blackboard

• A protractor, duct tape, metric ruler, simulated blood, index cards, and a chalkboard

• A compass, duct tape, metric ruler, real blood, index cards, and a whiteboard

What is the first step in setting up the experiment?

• Set up the protractor at the edge of the table

• Label the index cards with your name and table number

• Calculate the desired impact angle

• Flip over the whiteboard and tape two index cards side by side

How do you calculate the desired impact angle?

• Subtract the assigned angle from 90 degrees

• Add the assigned angle to 90 degrees

• Multiply the assigned angle by 90 degrees

• Divide the assigned angle by 90 degrees

What should you do after dropping the first set of blood drops?

• Calculate the height and width of the blood drops

• Reset the whiteboard to the next calculated angle and perform the steps again

• Answer the analysis questions on the back of the sheet

• Remove the index cards and allow the next group member to perform the lab

When measuring the height of a blood drop, what should you avoid including?

• The angle of the drop

• The tail of the drop

• The color of the drop

• The width of the drop

Where should you record the height and width measurements for drop one?

• On a separate piece of paper

• On the back of the index card

• In trial one of the data sheet

• In trial two of the data sheet

What is the next step after calculating the average of the measurements?

• Answer the analysis questions on the back of the sheet

• Record the measurements on the data table

• Divide the width by the length to calculate the ratio

• Use simple trigonometry to calculate the actual angle of impact

What mathematical concept is used to calculate the actual angle of impact?

• Algebra

• Calculus

• Geometry

• Trigonometry

What should be done once every group member has completed their part of the lab?

• Answer the analysis questions on the back of the sheet

• Clean up the lab area

• Submit the data sheet to the teacher

• Discuss the results with the group

What is the purpose of dividing the width by the length in the calculations?

• To measure the angle of the blood drop

• To determine the height of the blood drop

• To calculate the ratio

• To find the average of the measurements