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 the width of an object with a slider to control the width of the object and simple drag action to control the position of the object.

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

A test tube (Pink) for depth measurement via the depth probe.

Visual Elements

Outside jaws: used to measure the external diameter or width of an object (Blue).
Inside jaws: used to measure the 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 place in mm.
Retainer: used to block the movable part to allow 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 place 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/input field 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.

Others