Stephan Barry Wed, Dec.
201st period Kinetic And Potential Energy Lab ReportIn this lab, we investigated the relationship between energy, the capacity to do work, and motion. The two types of energy that were present during this experiment were elastic and kinetic energy. Elastic energy is potential energy that is stored as a result of the change in stretch of an object such as a spring being stretched. Kinetic energy is the energy of motion which refers to any objects in motion, such as the cart moving once the tension in the spring was released. We were able to calculate the work or energy done in this lab and calculate the velocity as well by using a motion detector to measure the motion that the cart (0.
5 kg) experienced once it was released. The cart experienced both elastic energy from the stretch of the spring, and kinetic energy as a result of letting go of the cart which is also known as velocity. A spring was hooked onto our cart and was then attached to the end of the ramp.
To set up our experiment, the motion detector was hooked up to our laptop with the program called logger pro. We then proceeded to calculate the velocity of the cart starting with a displacement of 0.05 meters. Once we collected the data, we continued this process by increments of 0.05 meters until we reached 0.5 meters which took ten trial runs.
We compared the Velocity (Vmax) to energy (J) and also compared the Velocity Squared (Vmax2) to energy (J). The graph of Vmax vs. Energy is linear and measures kinetic energy which is hookean.
The graph of Vmax2 vs. Energy is quadratic and measures elastic energy which is non-hookean. Our claim was as as energy increases, the motion increases quadratically meaning that there is a direct relationship between energy and motion. Our hypothesis proved to be correct because Hooke’s Law states that the relationship between the force of an object and its stretch are directly related.
To calculate the energy and motion of the cart, we needed to use an important formula to determine the energy of the cart once the spring attached to it was released. To get the data for the work that was done during this lab, we used the equation: A=1/2*k*(?x)2 . “A” is the area and represents the work or change in energy that the cart experienced. “k” is the strength of the spring and is measured as 10 N/m (Newtons/meters). “(?x)2” is the displacement of the cart and represents the elastic energy that was experienced. Energy is also referred to as work or force. It is measured in units of Joules (J).
Our first graph, Vmax vs. Energy, shows this relationship as it is a quadratic graph. Our claim was correct and there is a direct relationship between energy and motion. In this graph, it shows that the velocity is referred to as Vmax. Vmax is the maximum velocity and is measured in the units of m/s (meters per second). To calculate the velocity (Vmax), we used the motion detector that was connected to logger pro and found the velocity by highlighting the smoothest part of the slope on our laptops. We then collected this data for the entire ten runs that we did during this experiment. To calculate Velocity squared (Vmax2), we just squared the data that we collected for the Velocity (Vmax).
Our final equation for the graph of Vmax vs. Energy was y=0.324x-5.018*10-4.
Our slope was 0.324 N/m which represents the cart’s mass. The class concluded that as speed increases, energy increases quadratically. We also concluded that Kinetic Energy=1/2 *m*v2 (KE=½*(mass)*(velocity squared) and the Energy of the Spring=½*(k)*(?x)2. The class also agreed that the energy that made the cart move came from us when we stretched the spring and that energy went to the cart resulting in its movement. In this experiment, some errors that we could have made might have been that our overall class average for the slope of our carts were around 0.32 N/m.
The cart was supposed to be 0.5 kg but the data we collected may have been off. One reason our data could have been inaccurate is if we put our hand in front of the motion detector in order to stop the cart from falling off the ramp after the spring was released. This would have caused our data for velocity (Vmax) to be inaccurate. The motion detectors pick up all movements so by putting our hand in front of the sensor could cause our data to be off.
Another error that may have occurred is inaccurately measuring the displacement of each of the ten trials that we did. This would result in erroneous data. If we didn’t measure the displacement accurately, the cart could either have a greater or smaller distance to travel which would change the velocity. Therefore our data on our graphs would also be inaccurate.