### Mechanics

Schematic of system

1. Leveling screw, 2.Guide rail, 3. Slider, 4. Scaled post, 5. Mark plate, 6. Swing ball, 7. Electromagnet, 8. Armature, 9. Swing string, 10. Lock screw, 11. String adjust screw, 12. Swing post, 13. Collided ball, 14. Ball support, 15. Slider, 16. Tray

## LEMI-25 Apparatus of Collision and Projectile Motion

Features

• Clear physical phenomena

• Stable and reliable

• Affordable

Introduction

Collision between objects is a common phenomenon in nature. Conservation of energy and momentum are important concepts in mechanics. This experiment of collision and projectile motion studies the collision of two balls, as well as the swing motion of the ball before collision and the projectile motion of the other ball after collision, and uses the learned laws of mechanics to solve the actual problem of projectile.

If the final hit position of the collided ball is designated on the ground, the height of the swing ball can be calculated theoretically.  From the difference of hit positions between the theoretical calculation and the experimental result, the energy loss of the collision can be calculated, and by correcting the height of the swing ball, the final hit point can be accurately targeted to the designated position. This experimental apparatus has the following features:

1) The rail is made from aluminum alloy with high strength; the scales on both the rail and the slider are on the same plane to eliminate parallax errors.

2) The ball supporting rod has a conical flat top with weak magnetism. The ball can be stably positioned in the center of the flat top and the frictional resistance after collision can be reduced due to the small contact area.

3) Well position control and adjustment of components ensure repeatable experimental results.

The instruction manual contains experimental configurations, principles, step-by-step instructions, and examples of experiment results. Please click Experimental Contents to find more information about this apparatus.

Main Parts and Specifications

 Description Specifications Scaled post Scale marked range: 0 ~ 20 cm, with electromagnet Swing ball Steel, diameter: 20 mm Collided ball Diameter: 20 mm and 18 mm, respectively Guide rail Length: 35 cm Ball support post rod Diameter: 4 mm Swing support post Length: 45 cm, with height adjustable swing ball hanger Target tray Length: 30 cm; width: 12 cm

Part List

 Description Qty Guide rail 1 (with 2 leveling screws) Slider 1 1 (for holding scaled post) Slider 2 1 (for holding scaled post) Scaled post 1 Swing ball hanger assembly 1 (with lock screw, height adjust screw, swing string & swing ball) Electromagnet 1 (with armature, mark plate, switch box) Swing post 1 Collided ball 2 (diameter: 20 mm and 18 mm, respectively) Target tray 1 Line level 1 Carbon (graphite) paper 1 set DC power supply 1 (DC 6V) Instruction manual 1 (PDF)

Schematic of system

1. Leveling screw, 2.Guide rail, 3. Slider, 4. Scaled post, 5. Mark plate, 6. Swing ball, 7. Electromagnet, 8. Armature, 9. Swing string, 10. Lock screw, 11. String adjust screw, 12. Swing post, 13. Collided ball, 14. Ball support, 15. Slider, 16. Tray