This screencast shows how blood droplets are held together by a strong cohesive molecular force that produces surface tension in each drop and on the external force. Surface tension pulls the surface molecules of a liquid toward its interior, decreasing the surface area and causing the liquid to resist penetration.

Learners review surface finish basics and read how to calculate the roughness average.

Students take a quiz to test their knowledge of surface finish.

Learners examine the symbols and values that control surface roughness, waviness, and lay. A brief quiz completes the object.

In this module, you will see the derivation of the total surface area formula for a cylinder and work through several application problems.

This screencast, we see how the shape of a stain defines the angle of impact. In general terms the more circular the stain, the more perpendicular will be the angle at which it struck the surface. The more elliptical the shape of the stain, the more acute the angle will be. With practice and experience, the analyst can recognize the general angle of impact based solely on the shape of the stain.

In this interactive object, learners demonstrate the proper tightening sequence for mechanically joining two mating surfaces.

In this interactive object, learners test their knowledge of 14 geometric tolerance control symbols.

In this screencast, the student will learn that regardless of the surface onto which a blood droplet is falling, the angle or velocity at which it does so, or the volume of the droplet, there are four distinct phases involved in the reaction of a moving droplet with impact against a surface.

Learners study the properties of a rectangular solid and use geometric formulas to find volume and surface area.

Learners study the properties of a right circular cone and use geometric formulas to find volume and surface area.

Learners study the properties of a right circular cylinder and use geometric formulas to find volume and surface area.

Learners study the properties of a sphere and use geometric formulas to find volume and surface area.

Learners study the properties of a cube and use geometric formulas to find volume and surface area.

Learners study the properties of a regular square pyramid and use geometric formulas to find volume and surface area.

This document gives the procedures for layout on the surface of material.

In this animated print reading exercise, the learner calculates missing dimensions and identifies surfaces on projected views.

The learner will be able to see bacteria growth on common medical office surfaces.