Impulse Lab

Big Question: What is the relationship between impulse, force, and time during a collision?

                                                                       Design:

In this lab, the necessary materials were a force-probe ring stand, one sonic range finder, a red cart, and a track slide. The empty red cart was thrown towards the force-probe attached to the ring stand. The cart collided with the force probe. Then, the sonic range finder measured the data and, using the LabQuest device, put it into s Force vs. Time graph. Our group also recorded the cart's velocity before and after the collision.

                                                                      Reflection:

The data found in our experiment was calculated with the equation for Impulse (J=Pafter-Pbefore). P is the symbol for the momentum (Mass xVelocity). As usual, human error and technical difficulties played a small role in the experiment and has a slight effect on the data. We concurred that greater time minimized the impact of a force. The above diagram illustrates the interwoven relationship between impulse, force, and time.

                                                       


                         Real-World Connection:

A bat hitting a ball is an appropriate real-life example of impulse. This is a change of momentum, and momentum is mass times velocity, so any real-life situation where there's a change of velocity (acceleration) there's an impulse.

Collisions Lab

 Big Questions of Experiment:

"What is the difference between the amount of energy lost in an Elastic Collision vs. Inelastic Collision?"

"What is a better conserved quantity- momentum or energy?"

                                                                Design:

This lab involved the examination of three different types of collisions: elastic, inelastic, and explosions.The necessary tools utilized for this endeavor included the LabQuest device, two sensors, two 250g carts with velcro and a spring launcher, and a track. For the elastic collision, the two carts were sent towards one another with the spring launcher bearing the brunt of it, and causing the carts to bounce off. Next, the inelastic involved a similar process yet the velcro was used, so that both carts would stick together. Finally, for the explosion, both carts were originally attached by the velcro and then violently separated as the spring launcher was activated. The sensors detected the force at different points of the collision and sent the data to the LabQuest. We recorded the data from the device to our iPads using the collision sheet template.  

              Reflection:                                                           

To help analyze the data, two formulas were used, P=mv to calculate momentum and KE=1/2mv^2 for kinetic energy. Through our calculations, it was determined that momentum is a better conserved quantity and that, overall, conservation of energy occurs more in an elastic explosion compared to inelastic. Human error, as always remained a factor, yet technical difficulties were minimized due in part to greater experience with the equipment. 

                                                      

                                     Real-World Connection:

A collision between two cars can be best described as an inelastic collision. If an accident is severe enough, the two cars come together as one pile of wreckage.

                                                                                                                   

A video that puts into simple terms the difference between elastic and inelastic collisions.