March 10, 2009: Projectile Motion

Hey this is Darryl L.

In Today's Physics class we started off by listening to another Physics music called "Harry the Human Cannonball". Its another one of those songs that explains this time projectile is used as a theme for the story being told. Using physics a man calculates his trajectory aiming himself to intersect a lady on a trapeze as she falls in a net. There he aims and fires out of a cannon and in mid air catches the lady and lands in the net.

Next we did another lab involving 2 pennies and a ruler:

Step1: with 2 pennies place near the edge of the desk at a little distance apart from one another and the ruler placed behind them. You must push both of the pennies at the same time with the ruler and pay close attention to where the pennies land and the sound they make. Do this trial again but with different amount of force pushed on the pennies and again pay attention to where they landed and the sound they made.

Step 2: place both pennies again near the edge of the table. This time using the ruler at one end is placed near the edge of the desk and held down. Using the other side of the ruler you must push the pennies off the table. Repeat the steps using different amount of forces and keep track of where it landed and the sound they made.

You will notice that slide one is a diagram to show the motion of the pennies that were moved in step 2.

Slide 2 are formulas derived from the very first formula in green that can be used to help with projectile motion problems

On the Final slide is a diagram showing the time it takes for a projectile to reach its maximum height and which it equals the same amount of time for it to fall back down.

One last thing, we received another project involving us to build a catapult! A small catapult able to launch a ping pong ball across from one table to another (which if i heard right is about 80 cm). This project is due 7 days from today and is judged by the accuracy of the catapult and not by how far it can shoot the ping pong ball.

Well that's mostly what we did today in physics, if anyone else has something to add leave a comment and ill try to add or fix if anything is wrong or missing.

The next scribe i choose is kristina, good luck.

D-S skyline out.