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Purpose: The purpose of this lab is to predict where a projectile will fall when dropped from a known hight.

Summary: Given an initial height of a table plus an incline plane (1.027m) a projectile was dropped from the incline plane. The height (1.027m) was then used to calcualate the time it would take for the projectile to hit the ground (1.027= .5(9.8)t2, t= .457s). Once the height (1.027m) and the time (.457s) were found, it was then required to find the value of Vx or horizontal velocity (Vx=.0376m/.457s= .082m/s). Vy or the velocity in the vertical direction was found (9.8= (Vy/.457)= 4.47m/s). The height was then changed to 1.30m and using the data from the first experimental procesdure, a prediction of where the projectile will hit from the new hight (1.30m) was made. (1.30= .5(9.8)t2, t=.515s). Knowing that Vx will not change, the prediction was found by using d=v(t), (d= .082(.515)= .041). The mathematical prediction was found to be .041m. After this was tested experimentally and it was found that the distance the projectile traveled was .038m. A calculation of % error was then determined to be 7.59% ( (|.038-.041|/ [.038+.041]x200=7.59)

Procedure:
The first step is to measure the height (m) that the object is to be dropped from "H". Use this height to calculate the time it would take for the object to drop.
Once the height is determined, it is now necessary to determine experimentally the value of Vx or the celocity in the horizontal direction. This is equal to the time the object is in the air and the distance traveled from the base of the table.
Carbon paper will now be placed on the floorso that the location of the dropped object can be obtained. the object is rolled off the height and will mark the carbon paper. Record the distance the object fell from height "X". Calculate Vx using the distance from the known height and the calculated time for the object to fall.
Using Vx and the angle of the drop, calculate V and record this on the data sheet, also calculate Vy and record on the data sheet.
Now change the height of the fall by at least 12-18 inces and mark the floor predicting where the ball will now fall. Make sure you do not change the angle of the launch ramp. Again use carbon paper to record the actual fall.
Once the prediction is made, drop the object. calculate the % error of the actual from the predicted.

Equipment Used:
Large Protractor Assembly (incline plane) for mounting Slotted Ruler for projectile
Ruler with groove
Small ball bearing
Carbon Paper
Meter stick
Masking tape
Calculator
Boxes (used for lifting incline plane to new height)

Data: Height1=1.027m Height2= 1.30m Time1=.457s Time2=.515s Vx1=.082m/s Vy1=4.47m/s distance=.041
Calculations:
-Initial height of table + incline plane=