Learn Physics – Mr. Trampleasure
Resources for high school physics students and teachers
Write the equation for kinetic energy and for momentum.
As you watch the following video, take notes in your bookends sheet (use the Friday row and the “Three things I learned…” section). You should be able to describe the phrase “crumple zones” as it relates to cars.
Hi all. I’m out for another day or two (extreme sore throat, no, not caronavirus!) From the feedback I’ve received on Remind, it looks like most groups have completed, or are successful at gathering, the data.
Please take Monday to complete gathering data and entering it into a spreadsheet.
I’m proud of you all working together to figure out how to work the photogates and collect the data. It’s unusual for you to have this many days without your regular teacher, and it seems you are doing a great job.
It looks like some of you tried to copy the spreadsheet template on Friday, but were not logged in to your school account. I have set the sharing so you can now access it from any Google account. Click here if you need it.
Today: Enter a link to your spreadsheet in the form at the bottom (even if you have not completed it).
Please finish data collection for both collisions an explosions. Remember that an explosion uses the spring on one cart, and both carts start with zero momentum.
Analyze all your trials, calculating the momentum and kinetic energy changes for each scenario. If you would like, you can use a Google spreadsheet template here.
Each member of the group needs to make their own spreadsheet. If you prefer to use Excel, you can download the Google Sheet as an Excel spreadsheet.
Complete all the data analysis in a spreadsheet, and develop a conclusion about the conservation of momentum and kinetic energy in each of your scenarios.
Yesterday you had time to develop your skills at collecting data with the Vernier Photogates and/or Motion sensor. Today it’s time to collect the data.
Review your lab goals and procedures from Tuesday’s description. Your goal today is to collect pre- and post- collision data for both of your carts in four different variations (e.g. changing the mass, changing the velocity, changing the direction of the cars).
These labs will take about three days to complete. Tuesday will be preparing/practicing. Wednesday will be completing Part 2 and 3. Thursday will be sharing your trends/conclusions with the class, where we will look for overall trends/conclusions.
You will be provided with two carts and various masses. You will need to measure the speed of the carts right before they collide and right after they collide.
Explosions are defined as interactions where the initial velocity of each cart is zero.
Repeat the steps you used for Part 2
Momentum is a conserved property of a system. This conservation can be demonstrated by using Newton’s third law (Fa/b = -Fb/a) to develop the equation:
mΔva + mΔvb = 0
Momentum is given the lowercase p as its symbol.
The change in momentum (Δp) of an object is defined as impulse.
Impulse = Δp = mΔv = FΔt
Keep in mind that while momentum depends on the same variables as kinetic energy (mass and velocity), momentum and kinetic energy are not the same thing. Momentum is always conserved, but, while energy is conserved, it can move from kinetic storage storage to gravitational, elastic, thermal, etc.