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 examine the circuitry in a DC variable speed drive that prevents the motor from running at 0 rpm or at maximum speed under certain conditions.

In this animated activity, learners examine the firing circuits in a DC variable speed drive. The circuits cause the current flow through the armature and rpm to vary. This activity has audio content.

The learner will understand the design of a planetary gear drive and its advantages and disadvantages.

The learner will gain an understanding of the inner workings of the cycloidal gear drive while watching a video and listening to an explanation of its features.

In this interactive object, students read how to calculate the blank size for cylinders in a three-roll pinch roller. A calculator is required for the brief quiz that completes the activity.

In this learning activity you'll discover how the Eagle Power Roller control panel operates.

Students follow steps to determine the number of inputs that can be driven by a specific IC. A sample problem is given.

Learners view an animated explanation of why an adjustment of the output voltage by an AC drive is required to maintain a constant torque as the frequency is varied.

In this learning activity you'll review the parts of a three-roll power roller and practice identifying them.

In this learning activity you'll review the safety considerations for persons using the power pinch roller and take a short quiz.

In this animated and interactive object, learners follow steps that begin with choosing the correct drive roll and include feeding the electrode wire from the spool to the welding gun.

The learner will identify the steps and proper techniques for installing a wire spool on a welding machine.

In this animated lesson, learners examine the rectifier circuitry in a DC variable speed drive that supplies the voltages to the field coil and armature.

In this animated activity, learners examine the circuitry in a DC variable speed drive that keeps the motor running at a constant speed as the load varies.

Learners watch a video and an animated depiction of the operation of the feed section of a corrugated press. They also read descriptions of the feed table, side guides, feed wheels, feed gates, and the feed roll.

Learners examine the speed control circuits in a DC variable speed drive that cause the RPM of a motor to vary. This activity has audio content.

In this animated activity, learners examine the circuitry in a DC variable speed drive that causes the motor to accelerate or decelerate at slow rates. This learning object has audio content.

Learners examine the circuitry in a DC variable speed drive that protects the rectifier diodes and motor windings from being damaged due to excessive current.

In this animated and interactive object, learners examine why the voltage produced by an AC drive must be increased when its frequency is increased due to inductive reactance.