Project : Analysis of Projectile Motion

Introduction :

When a ball or other object is thrown in a horizontal direction at some angle. The ball travels in a path described by a parabola. (See Graphic Below)


The ball is traveling in the x direction with a constant velocity but a changing velocity in the y direction.

Find the velocity of the ball in the X direction by taking the difference between the x values of each point (X). Then take the average of the X's and divide by the time interval (t).

Find the acceleration of the ball in the Y direction by taking the difference between the y values of each point (Y). The take the difference between the Y's or (Y). The find the average of this value and acceleration by dividing the (Y) by t².

Instructions:

1. Label the lines and axis on the photograph
   1. The x axis is 5 cm between each line.

   2. The y axis is 1 cm between each line.

2. Label each point on the photograph and determine its x and y values as accurately as possible.

3. Construct a spreadsheet for this data using the columns in the table below as a template .
   1. Label the columns as indicated in the table below. Enter the numbers from one to fourteen into column of the table.

   2. Enter the x and x coordinates from the photograph into columns two and three in the table.

   3. In the fourth column (X), enter the formula to calculate the difference in X values between adjacent points (X). In the first row enter the formula for X₂- X ₁. If that formula is correct, copy it down for the remaining 13 rows.

   4. In the fifth column(Y), enter the formula to calculate the difference in Y values between adjacent points (Y). In the first row enter the formula for Y₂ - Y₁. If that formula is correct, copy it down for the remaining 13 rows.

   5. In the sixth column(( Y)) enter the formula to calculate the difference the values in the values between values in the Y columns. In the first row enter the formula for Y₂ - Y₁. If that formula is correct, copy it down for the remaining 12 rows.

   6. In the first row of the seventh column place the time interval between the flashes of light.

   7. In this case it is 1/120 second.

   8. Find the average value of the fourth column(X). Use the @avg() function. In the next cell below the average X, calculate the average velocity in the x direction by dividing the value in the average X cell by the value that is in the first row of the seventh column (1/120 sec).

   9. Find the average value of the sixth column((Y)). Use the @avg() function. In the next cell below the average (Y), calculate the average acceleration in the direction by dividing the value in the average (Y) cell by the value that is in the first row of the seventh column (1/120 sec) squared.

      The time between each strobe light flash is 1/120 sec.

      This should be the acceleration of gravity 9800 cm/sec².

   Number	X Coordinate	Y Coordinate	Delta X ( X2-X1)	Delta Y (Y2 - Y1)	(Y) DY21 -Y32)
   1
   2
   3
   ...
   9
   10
   11
   12
   13
   14
   		Ave (X)		Ave (Y)
   		Vel X = x/t			Acc = (Y)/ t2

   Plotting the Data :

   Construct a single graph that will have three different Y series plotted against X.

   1. Choose the New chart option from the chart menu option.

   2. When the series box appears, choose column two (X) of the table as the X series.

   3. Choose the third column (Y) of the table as the 1^st series.

   4. Choose the fourth column (Y) of the table as the 2^nd Y series.

   5. Choose the fifth column ((Y) of the table as the 3^rd series.

   6. Display the graph (make sure the type is X-Y plot).

   7. Complete the graph by adding the Title to the graph and the titles to the X and Y axis.

   8. When the graph is complete, insert the a copy of the graph in the spreadsheet below the table built above.

   9. Print out a copy the spreadsheet and graph to hand in.

   A copy of a photograph of the projectile motion with a 1/120 sec strobe light.