### Mechanics

Schematic of system

1. 1. Base line

3. 3. Support

4. 4. Specimen

5. 5. Lever

6. 6. Magnet mount

7. 7. Magnets

9. 9. Weights

Hall sensor and magnets

## LEMI-12 Young's Modulus Apparatus - Hall Sensor Method

Features

• Hall micro-displacement sensing

• Hall element

• Simple structure and stable performance

• High accuracy (error<3%)

• Ideal demonstration system

Introduction

When rigid materials are subject to particular stress or forces, deformation (compressed, twisted, stretched, etc) may occur. For many materials, when suffered from force or stress, the resisting or restoring force that tends to return the material to its original shape is proportional to the deformation. Young's Modulus, E, is a constant that describes the material's mechanical property of stiffness and is expressed as the ratio of stress to strain for a material experiencing tensile or compressive stress.

This apparatus is designed to study the deformation characteristics of thin metal sheet specimens under load. Deformation is created by applying a small force F on the sheet. A micro-displacement sensor based on Hall effect is used to measure the deformation, where the output voltage is proportional to the amount of displacement.

Using this apparatus, the following experiments can be conducted:

1. Understand the principle, structure, properties and applications of a Hall displacement sensor

2. Measure the Young's modulus of a copper specimen

3. Calibrate a Hall displacement sensor

4. Measure the Young's modulus of a malleable iron specimen

Main Specifications

 Description Specifications Reading Microscope Range: 8 mm; resolution: 0.01 mm; magnification: 20X Weights 10.0 g and 20.0 g Digital Multimeter 3-1/2 digit; range: 0 ~ 2000 mV Specimens Copper and malleable cast-iron sheets Relative Uncertainty of Measurement < 3%

Part List

 Description Qty Main Unit 1 Stand Rack 1 Reading Microscope 1 Hall Sensor 1 Cable 1 Weights 8 pcs (10 g), 2 pcs (20 g) Manual 1

Schematic of system

1. 1. Base line

3. 3. Support

4. 4. Specimen

5. 5. Lever

6. 6. Magnet mount

7. 7. Magnets