General Description

This JavaScript App simulates the Vernier Caliper. The simulation shows the instrument setup with a rectangular object .

The Vernier calipers model has an object (Blue) for the internal jaws to measure width of an object with slider to control width of the object and simple drag action to control position of object.

An object (Green) for external jaws to measure internal diameter of a cylinder for example with slider to control dimensions of the cylinder.

An test tube (Pink) for depth measurement vai the depth probe

Visual Elements

Outside jaws: used to measure external diameter or width of an object (Blue)
Inside jaws: used to measure internal diameter of an object
Depth probe: used to measure depths of an object or a hole ( not shown in this model) .
Main scale: gives measurements in mm.
Vernier gives measurements up to one decimal places in mm
Retainer: used to block movable part to allow the easy transferring a measurement ( not shown in this model)
fine control buttons for learners to manipulate the model with single incremental precision control
Vernier gives measurements up to one decimal places in mm

Controls

ComboBox 1: Sets the type of caliper scales.
ComboBox 2: Show and hide hints, answers, common objects etc
ComboBox 3: Sets the zero error
play button to run the caliper to move automatically.
reset button to bring simulation back to original (default) setting.
?= click to toggle between combobox or input field.
combobox/inputfield to ease selecting answers like 0.00 and key in numbers.
cm/mm text click to toggle between the 2 units, centimeter and millimeter
double click on the screen to go full screen, especially useful on mobile browsers
drag on the screen reposition, especially useful on mobile browsers
pinch in/out to zoom in/out, especially useful on observing the vernier scale readings
menu to show or hide the control panel