2-18-09

Cory Miller We started off the day by going over the homework and checking it. Mr. Manning checked question 4 and 8. The questions were about speed on a frictionless ramp. If a block starts at the same speed of another block then it reaches the end of the ramp with the same speed no matter how steep the ramp is. The daily question of the day was asking what the speed of the cube is of all blocks start at the same height but the steepness of the ramps change. To find the answer you put the Potential Energy at the top equal to the Kinetic Energy at the bottom. Which is the same as mass times gravity times the height equal to one half times mass time the velocity squared. The masses on either side cancel out to give you gravity times height equals one half times the velocity squared. Then you just plug in the numbers to give you 9.8 meters per second times 5 meters equals 1/2 times the velocity squared. You multiply and devide to give you 98 equal to the velocity squared. Then you just take the square root of each side to finally give you the velocity of 9.8 meters per second. At the end of the peroid we started a lab called the Simulation Activity and we will finish it up tomorrow.