Lab 3

1.      Lab 3: Non-Constant acceleration problem/Activity

a.      Lab conducted by Mohammed Karim, Curtis, and Lynel on September 12, 2016

2.   

   Objective – Learn how to better use Excel.

3.    

  Theory/Introduction –

        In this lab, we are presented with the scenario that a 5000-kg elephant on frictionless roller skates is moving at a rate of 25 meters per second. The elephant has a 1500-kg rocket that generates a constant 8000 N thrust to slow it down. We are tasked with finding out how far the elephant goes before coming to rest.

        First, we are walked through an analytical approach that uses multiple integrals to move from acceleration to velocity and finally distance. This approach then calculates when the velocity is zero to find out time and plugs it back into the distance equation, which is a function of time. The solution tells us that the elephant will stop at 248.7m. We are able to solve this, but after a lot of work.

        Rather than going through this, we simply used Excel to find out the answer. We plugged in values for the weight, velocity, thrust, force, and time and were given the answer back effortlessly.

4.   

   Apparatus/Experimental Procedure

The only “apparatus” used was Microsoft Excel. This program was used to input our values and distance was given.

5.  

    Data Tables

a.

6.     

Explanation/Analysis

Our data included the excel document. For values that we did not know directly, we entered in equations that would give us the answers and filled it down. As for time, to get a much closer value, we put smaller and smaller periods. For a more precise answer, we set the period to every 0.1 seconds.

7.      

Conclusion

As fun as it is to solve integrals and spend almost an hour painstakingly dealing with algebraically complex equations, it was much easier to use Excel, a program that will deal with all the hard work for us. If we input the values, Excel outputs the values. We knew that the time interval was small enough in that the value matched with the analytical value. Had we not had the analytical value, we could have just made it small enough to find multiple unchanging intervals. This indicates that our value is very precise.