The concept of pressure and energy can be understood better through the example of pressure cooker. Pressure cooker animation gives an insight into the molecular level interplay of energies and forces . Also included are sections on design and advantages of pressure cooker. This kind of explanation using animation is the only one in the world. It is very useful for industry and schools.

The animation works at two levels - macro and micro
At macro level it gives an insight into structure and design of a pressure cooker, its parts and their description; its advantages, principle of working etc.

At micro level it explains the concept of boiling and how molecule interact with each other to create "pressure". The mechanism of boiling in an open pan, closed pan and further explanation based on momentum. Bonds in water and how are they affected by energy.

It links observed phenomenon to unseen molecules, it correlates

• Boiling ----Molecular bonds & their energies
• Pressure ---- Collision of molecules --- Conservation of momentum
• Bubbles formation in boiling --- Vapour molecules of water
• Heat --- Energy transfer between flame, metal atoms and water molecules
• Atmospheric pressure --- Effect of gravity
• Effect of atmospheric pressure --- Collision of air molecules.

The detail of the content covered and questions answered in animation format and in our explanatory notes are as follows:

Pressure cooker

• Principle
• Design
• Methods of release of pressure ( in EN)
• Parts
• History ( in EN)
• Safety feature ( in EN)
• Benefits ( in EN)
• Materials used in the manufacturing ( in EN)
• What is happening inside it when water is heated ?

1. Why does the temperature increase faster in a cooker than in an open pan?
   
   
2. Pressure cooker an application of Gay lussac's law
   
   
3. As the pressure goes on increasing, the temperature also rises faster (why)
   
   
4. How does superheated steam ensure faster and better cooking ?
   
   
5. Why boiling point of water changes due to pressure ? - based on change in molecular structure of water
   
   
6. Mechanism of boiling in open pan - based on inter molecular forces - energy exchange between metal & water - collision - momentum - kinetic energy correlation
   
   
7. Why do the H2O molecules that have broken free start rising to the top ?
   
   
8. Why does boiling take place when vapour pressure = atmospheric pressure ?
   
   
9. What has kinetic energy and collisions got to do with it ?
   
   
10. Does boiling take place only at the surface of liquid?
    
    
11. Complete story told in step-by-step of what happens to the molecules, energy and collisions as the temperature graphs rises from 27--80--100 --100+
    
    
12. How do air molecules exert pressure on the water vapour ?
    
    
13. Do the bubbles formed in boiling at the base contain air ?
    
    
14. How is boiling affected in a closed pan ? - Pressure changes
    
    
15. Why boiling point increases in a closed pan ? - water vapour molecules
    
    
16. Equilibrium state in closed pan
    
    
17. Temperature - pressure relationship under constant volume.
    
    
18. Generation of high pressure inside pressure cooker - complete explanation done on the basis of momentum, collisions, Newton second law of motion and conservation of momentum.
    
    
19. Momentum explained by an example
    
    
20. Why pressure goes up when more gas is added to a closed container ?
    
    
21. what would happen if the walls of a cooker are made up of thinner material ?
    
    
    
22. why pressure cooker is a boon to those living at high altitudes?
    
    
23. Why Boiling point decreases with an increase in altitude ? Why atmospheric pressure decreases with altitude ? what it has to do with gravity ?
    
    
24. How can water boil at room temperature?
    Case 1) heat at definite pressure
    Case 2) reducing pressure
    
    
25. Why is steam so efficient in cooking? ( in EN)
    
    
26. Superheating water allowing it not to boil till 118 deg C under normal conditions.( in EN)
    
    
27. Nucleation ( in EN)
    
    
28. Exploding water ( in EN)
    
    
29. Difficulty in boiling water in microwave oven ( in EN)
    
    
30. Superheating water on a ordinary stove ( in EN)
    
    
31. Why does water boil when a solid is introduced in it ? ( in EN)

( EN = Explanatory notes)

• Properties
  
  
•  Concept of Density
•  Concept of energy variation during phase change
•  Concept of Internal energy
•  Concept of pressure
•  Heat and Temperature - Kinetic theory of matter
•  Maxwell Boltzmann Distribution law
•  Potential and kinetic energy