Impressions

Question 1

Tyre impressions

Answer 1

determines where the vehicle is heading

Question 2

Footwear

Answer 2

• determines if the person is running or walking
• heel first, sole second: person is heading to the right
• sole first, heel second: person is heading to the left

Question 3

Photograph

Answer 3

• first step in preserving an impression

- using natural lighting or automatic flash should be taken with an angled light source

Question 4

Making a cast

Answer 4

• fairly large impressions can be made using plaster of Paris.
• with smaller impressions, a pad of quick setting plastic can be used.

Question 5

Factors that depend on the choice of materials used for making the cast

Answer 5

• where the impression is located
• under what conditions the material will set
• how much detail is required

Question 6

Plaster of Paris is made up of…

Answer 6

calcium sulfate monohydrate