Con and NonCon Force1234567123456123.pptx

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1. Conservative and Non-Conservative Forces Physics 1 - Grade 12

2. Introduction

3. Conservative Forces

4. Properties of Conservative Forces

5. Conservative Forces (energy is conserved, path-independent) Gravitational Force Example: Work done by gravity when lifting or dropping an object. Elastic (Spring) Force Example: Stretching or compressing a spring (Hooke’s law). Electrostatic Force Example: Force between two charges.

6. Conservative Forces (energy is conserved, path-independent) Magnetic Force (under certain conditions) Example: Work done on charges in a magnetic dipole system (though usually treated carefully). Central Forces (force directed along the line joining particle and center , e.g., gravity, Coulomb’s force).

7. In practice, we compare stored energies for different object positions. This means that only differences in potential energy are important; the zero level can be set wherever is convenient.

8. Non-Conservative Forces Definition: A force is non-conservative if the work it does on an object depends on the path taken. Examples: Friction, Air resistance, Tension, Applied force.

9. Properties of Non-Conservative Forces

10. Non-Conservative Forces (energy dissipated, path-dependent) These forces usually convert mechanical energy → heat, sound, deformation .

11. Non-Conservative Forces (energy dissipated, path-dependent) These forces usually convert mechanical energy → heat, sound, deformation .

12. 1. James lifts a box of mass 5 kg from the ground to the top of a 1 m high table. What is the change in stored gravitational energy? 1. Change in stored gravitational energy Δ Eg = mgh Δ Eg ​=5×9.8×1= 49J

13. 2. Chris pushes the end of an un‐stretched spring in by 10 com. The spring constant k = 3000 N/m. What is the change in stored elastic energy? 2. Change in stored elastic energy 15J

14. Comparison of Conservative and Non-Conservative Forces

15. Applications in Physics

16. Summary

17. 2. A spring with spring constant k=800 N/m is stretched by 5 cm. 1. Maria lifts a 3 kg book to a shelf 2.5 m above the ground. seatwork