02/26/14 Group experiment:Thermal expansion, Latent heat and Gas law experiment

The different materials have different thermal expansion after they heated.

Using the equation f=v / λ to find the frequency.

To determine the material of metal pipe by using steam generator to heat up the pipe.

The relationship and formula between angular displacement and temperature change.

The equipment used during the thermal expansion experiment.

Graph of Temperature vs Time and Angle vs Time by collecting the experiment data.

To find the uncertainty of diameter by using the thermal expansion rate formula.

Proving the equation of alpha with uncertainty of meter.

The equipment used during the latent heat experiment.

Prove the equation of m*L and P*t to find the latent heat Q.

Find the average latent heat by collecting each group's data.

Using the equation Q=mcΔT and Q=mL_f to find the mass of water by using Q_w =Q_I.

 _{Prove the equation to find the relationship between mass and area.}

The graph of pressure change vs the volume.

The graph of Pressure vs Temperature.

The equation of standard deviation.

The physical meaning of ideal gas:

Pressure comes into play whenever force is exerted on a certain area, but it plays a particularly important role with regard to gases. The kinetic theory tells us that gas molecules obey Newton’s Laws: they travel with a constant velocity until they collide, exerting a force on the object with which they collide. If we imagine gas molecules in a closed container, the molecules will collide with the walls of the container with some frequency, each time exerting a small force on the walls of the container. The more frequently these molecules collide with the walls of the container, the greater the net force and hence the greater the pressure they exert on the walls of the container. So, as the temperature increase, pressure increases. Otherwise, the pressure decreases, if the temperature decreases.

Conclusion:

The thermal expansion is the tendency of matter to change volume in response to a change in temperature, and the volume is directly proportional to the temperature. Latent heat is the energy released or absorbed by a body or a thermodynamic system during a constant-temperature process. A typical example is a change of state of matter, meaning a phase transition such as the melting of ice or the boiling of water which we did in the classroom. In ideal gas law, the temperature increase, the pressure also increases. The pressure decreases if the volume increases.