The purpose of this lab is for students to explore the work of spring when stretched from initial position and released at a certain distance from initial position.
Apparatus:
We place a motion sensor at one end of the track and a cart attached one end of the spring. The other end of the spring was attached to a force sensor at the other end of the track. The force sensor is held in place by a c-clamp that was screwed onto the side of the table. The middle of the spring was held up by a block to avoid any additional error. After collecting the data of spring work for the cart alone, we measured the work of the cart with mass on the cart.
Explanation:
We set Logger Pro to read the force from the force sensor and the distance with the motion detector. The cart, with masses on the cart, gave a total mass of 1.405 kg. As we pulled the cart away from the force sensor, the force sensor read about 3.7N of force. As we release the cart from the stretched position, we collected the data of force vs distance. With the mass and velocity known, we were able to calculate the kinetic energy. Using Logger Pro, we found the integral of the force, which gives us the work of the spring, giving us a value of 0.4484m*N. The total kinetic energy, measured by the equation we inputted in Logger Pro, 1/2mv2, was 0.394J. The percent error was 12%, which is considered quite large, knowing that the percent error is higher than 10%. There was large error accumulated when collecting data. For example, when the spring was contrasting, the wooden block was also pulled as well, causing friction between the block and the track. Another cause of high percent error was the force sensor was not reading a value of zero after calibrating the sensor.
In this lab experiment, we measured spring work using a force sensor and motion detector. We needed to find the force of the spring when the spring was stretched a certain distance, and the mass of the cart with masses in the cart. With all this, we were able to find the kinetic energy. Once we have force and kinetic energy, we compared the energy from the equation to the energy calculated from Logger Pro, giving us a percent error higher than 10%. There were too much error around the apparatus that we were not able to get a accurate reading.
