1. FORCES AND STRUCTURES
Force - the influence that tends to change the speed and direction of a stationary or a moving body. 
External Forces
Internal Forces

2. There are 3 types of Internal forces. 1. Compression. 2. Tension. 3
There are 3 types of Internal forces Compression 2. Tension 3. Shear

3. COMPRESSION - pushing or squeezing force TENSION – pulling or stretching force SHEAR - two parallel opposite forces applied at same point - causes tearing

4. Lets look at some examples of these internal forces in our daily lives

6. Tension

7. Tension

8. Tension

9. Tension

10. Tension

11. Compression

12. Compression

14. Compression

15. Compression

16. Shearing

20. Complementary Force