Projectile Motion

• Initial settings:
  • Set the initial vertical position of the cannon at the ground level
    • Set the angle at 80^o
    • Fire a shot and notice the final vertical position of the object, y_f. If y_f is positive, it means that final position of the object is higher than its initial. If y_f is negative, the the final position is lower than its initial.
    • Adjust the initial vertical position so that y_f is very close to zero. Repeat the previous step until |y_f| is less than or equal to 0.2 m. Write down in your notebook the final position.


• Activity 1: Investigate how the firing range depends on the initial velocity.
  • Additional Settings:
    • Make sure the Air Resistance box is unchecked. (Ignore Air resistance)
    • Set the firing angle at 65^o
  • Perform the experiment:
    • Choose an initial velocity v_o equal to 16 m/s
    • Fire a shot. Make sure the final position is within 0.2 m from the initial. If not, readjust the position of the cannon following the instructions in the "Initial Settings" section above.
    • In your notebook, write down the range and the time of flight.
    • Repeat the procedure for initial velocities equal to 18 m/s, 20 m/s, 22 m/s, 24 m/s, 26 m/s, 28 m/s, and 30 m/s.
  • In your lab notebook, write down the data in the following format:
    
    

    vo (m/s)	vo2 (m/s)2	R (m)	T (s)
    16
    18
    20
    22
    24
    26
    28
    30

    
    
  • Results:
    • Plot R vs. v_o². (Why do we plot R vs. v_o² and not R vs. v_o?)
    • Find the slope of the graph. You can use your calculator, spreadsheet, or you can go to this website. If you choose the latter, clear the data and type in your own data. The slope of the line is given by "m" in the box below the graph.
    • Determine the gravitational acceleration g from the slope. Calculate the percent error, 100% . |g_measured - 9.8|/(9.8)
    • If this is a virtual simulations, why do you think there is an error in the value of "g"? Is it random?