First law of thermodynamics

this is a presentation on first law of thermodynamics

1. Bangabandhu Sheikh M ujibur Rahman Science and Technology University A presentation on first law of thermodynamics Presented by Md. Shimul Bhuia St. ID: 16PHR003 Department of Pharmacy

2. Welcome

3. Thermodynamics Thermodynamics  is a branch of physics concerned with heat and temperature and their relation to energy and work .In particular, it describes how thermal energy is converted to and from other forms of energy and how it affects matter.

4. The first law of thermodynamics The first law of thermodynamics states that the amount of heat given to a system is equal to the sum increase in the internal energy of the system and the external work done.

5. Thermodynamics systems A thermodynamic system is the material and radiative content of a macroscopic volume in space, that can be adequately described by thermodynamic state variables such as temperature, entropy, internal energy and pressure

6. Statement of the first law of thermodynamics Conservation of energy Energy can neither be created nor destroyed but it can change forms Total amount of energy in a closed system remains constant

7. Description with formula Heat/work formula: Δ U=Q-W dU = Δ Q- PdV [W= PdV ]

8. Significance The total amount of energy in the world is constant. It is impossible to get more energy oyt of a system than is put into it. You can’t get energy from nothing.

9. Application Can be used to find the latent heat of vaporization It is used to calculate the quantity to raise the temperature of an ideal gas

10. Limitation of first law Limitation:- First law does not help to predict whether the certain process is possible or not. Reason:- It does not specify that heat cannot flow from low temperature body to a high temperature body Limitation:- The first law does not give information about direction . Reason :For example it puts no restriction on the direction of the flow of heat, whether heat can flow from a cold body to a hot body or vice versa.

11. Conclusion The 1 st law of thermodynamics simply says that the amount energy in a closed system remains constant. Regardless of how it is changed or is moved around. To add energy to a system it needs to come from some place else

12. Any Question?

13. Thank you