Physical Science Applications in Agriculture

1. Physical Science Applications in Agriculture Unit Physical Science Systems

2. Problem Area Agricultural Mechanics and Machine Systems

3. Safe Handling and Loading:Balance and Center of Gravity Lesson

4. What is a roll-over? • Discuss tractor safety and rollover protection. • Anyone personally aware of tractor rollovers. • Discuss loading and transport. • Have any of them dumped a load or heard of someone who has dumped a load?

5. Learning Objectives • Define stability. • Explain the center of gravity. • Calculate the center of gravity.

6. Terms • Balance • Center of gravity • Equilibrium • Stability www.galleri-bjorn.dk/.../pages/John%20Deere4.htm www.cdc.gov/

7. What is stability? • Stability • Refers to a condition of balance. • Center of gravity is critical to stability. • If an object is tipped, but will return to its original position when released, it is in stable equilibrium. www.alpaca-info.com/ranch.htm

8. What is stability? • For a stable equilibrium condition, a plumb line dropped from the center of gravity will fall within the base of the object. www.safetyline.wa.gov.au/.../lecture78/l78_03.asp

9. What is stability? • If an object is tipped to a point where a plumb line attached to the center of gravity falls outside its base, an unstable equilibrium condition exists. www.safetyline.wa.gov.au/.../lecture78/l78_03.asp

10. What is stability?

11. What is center of gravity? • Center of gravity • Point at which all parts or areas of a body are balanced. • Balance • Stability or equilibrium iareh.usask.ca/rhep/.../slide0004.htm

12. THE CENTER OFGRAVITY ON A TRACTOR

13. What is center of gravity? • The typical tractor has its center of gravity located between the front and rear wheels behind the midpoint of the tractor’s length and above the axle height. • Center of gravity of an object will always seek the lowest possible position. • If tipping an object lowers the center of gravity, the object will not return to its original position.

14. What is center of gravity? www.alpaca-info.com/ranch.htm

15. Where is the center of gravity located on a tractor? • Center of gravity of an object determines the stability of that object.

16. Where is the center of gravity located on a tractor? • The center of gravity will always seek the lowest position possible; therefore great care must be taken when loading or hitching to prevent rollover. • The external forces acting on a tractor pulling an implement can be quantified and analyzed.

17. Where is the center of gravity located on a tractor? • Hitch height is an important variable in stability. • If hitch height is too high, the hitched tractor is not in equilibrium. • Hitching at a lower point or weighing the front of the tractor can prevent unsafe rollover conditions from occurring.

18. Where is the center of gravity located on a tractor?

19. Where is the center of gravity located on a tractor? • The object will be stable if a plumb line dropped from the center of gravity passes through the base of the object.

20. Review/Summary • What is stability? • What is center of gravity? • Where is the center of gravity located on a tractor?