# Lab 4 Thermodynamics Essay

761 Words4 Pages
Thermodynamic Gravitation and Basic Roller Coaster Dynamic Report A – Terrestrial Gravitation Acceleration In this section, a mass was aligned over two photogates, and allowed to drop in free fall. The time of the free fall was recorded for two different mass samples. Data Obtained: Equations: x = 71.5 m x=xo+vot+at22 xo = 0 m a=2x-xo-vott2 vo = 0 m/s a=2(x)t2 theavy= 0.3755 s tlight= 0.3868 s Calculations: For theavy: a=2(71.5)0.37552 a=10.14 m/s2 For tlight: a=2(71.5)0.38682 a=9.55 m/s2 There are many possible errors associated with this experiment. One error is that the initial height of the mass was not exactly at the xo = 0 m point, since the mass was hung in place by a tied string. There also may have been shifting in the alignment of the photogates, and other equipment causing the measured value of x to be inaccurate. The mass may have been swinging slightly when it fell, causing it to fall on an angle instead of straight down. The quality of the data could be improved by ensuring that the mass was properly aligned at xo, prior to its free fall. Furthermore, the photogates could have been leveled off and re-aligned after each free fall trial. B – First Law of Thermodynamics In this section, two cars of varying mass were placed on a declining ramp and allowed to move as a result of gravitational forces. The time it took for each car to pass between two photogates at either end of the ramp was recorded for each trial. The first law of thermodynamics states that energy is conserved. This applies because the speed of the car was determined by the gravitational forces in place due to the slope of the ramp. In other words, the potential energy stored in the car at the ramp’s elevation was converted into kinetic energy as it moved down the ramp. The height of the slope was measured as 10.6 cm (0.106