ball toss report

Name:

Physics 111 ON 2

October 1, 2020

Lab #4 Ball Toss

Objectives:

· Collect position, velocity, and acceleration data as a ball travels straight up and down.

· Analyze position vs. time, velocity vs. time, and acceleration vs. time graphs.

· Determine the best-fit equations for the position vs. time and velocity vs. time graph

· Determine the mean acceleration from the acceleration vs. time graph

Preliminary Questions:

1. Consider the motion of a ball as it travels straight up and down in free fall. Sketch your prediction for the position vs. time graph. Describe in words what this graph means.

2. Sketch your prediction for the velocity vs. time graph. Describe in words what this graph means.

3.Sketch your prediction for the acceleration vs. time graph. Describe in words what this graph means.

Method:

First we connect the Vernier Motion Detector to the Logger Pro and then connect that into the computer. Then switch the motion detector to Ball/Walk and place it on the chair in a place to protect it. After that on the laptop we open the ball toss files and then press collect data and hold the ball around 0.5m above the motion detector and toss it between 0.5m to 1m above the motion detector and hold it after catching the ball. Make sure your hands are not picked up by the motion detector.

Data:

Figure 1 Ball Toss (Position, Velocity, and Acceleration vs. Time)

Figure 2 Region Where Ball is _____________________________________

Figure 3 Region (Below) Where Ball is ______________________________________

Figure 4 _____________________________ Point Labelled

Figure 5 __________________________ Labelled

Figure 6 Ball Toss

(Position vs Time with Curve Fit, Velocity vs Time with Linear Fit and Acceleration vs Time with Mean)

Data Analysis:

1. Print or sketch the three motion graphs. The graphs you have recorded are fairly complex and

it is important to identify different regions of each graph. Click Examine and move the

mouse across any graph to answer the following questions. Record your answers directly on

the printed or sketched graphs.

1. Identify the region when the ball was being tossed but still in your hands:

1. Examine the velocity vs. time graph and identify this region. Label this on the graph.

See Figure _________________

2. Examine the acceleration vs. Time graph and identify the same region. Label the graph.

See Figure __________________

2. Identify the region where the ball is in free fall:

1. Label the region on each graph where the ball was in free fall and moving upward.

See Figure ___________________

2. Label the region on each graph where the ball was in free fall and moving downwards.

See Figure _____________________

3. Determine the position, velocity, and acceleration at specific points.

1. On the velocity vs. time graph, decide where the ball had its maximum velocity, just as the ball was released. Mark the spot and record the value on the graph.

See Figure ______________________

2. On the position vs. time graph, locate the maximum height of the ball during free fall. Mark the spot and record the value on the graph.

See Figure _____________________

3. What was the velocity of the ball at the top of its motion?

The velocity of the ball was _______ m/s.

4. What was the acceleration of the ball at the top of its motion?

The acceleration of the ball is _______ m/s/s.

2. The motion of an object in free fall is modeled by y= ½gt2+v0t+y0 where y is the vertical

position, g is the magnitude of the free-fall acceleration, t is time, and v0 is the initial velocity. This is a quadratic equation whose graph is a parabola. Your graph of position vs. time should be parabolic. To fit a quadratic equation to your data, click and drag the mouse across the portion of the position vs. time graph that is parabolic, highlighting the free-fall portion. Click Curve Fit, select Quadratic fit from the list of models and click. Examine the fit of the curve to your data and click to return to the main graph.

3. How closely does the coefficient of the t2 term in the curve fit compare to ½g?

4. What does a linear segment of a velocity vs. time graph indicate? What is the significance of the slope of that linear segment?

5. The graph of velocity vs. time should be linear. To fit a line to this data, click and drag the mouse across the free-fall region of the motion. Click Linear Fit.

6. How closely does the coefficient of the t term in the fit compare to the accepted value for g?

7. The graph of acceleration vs. time should appear to be more or less constant. Click and drag the mouse across the free-fall section of the motion and click Statistics.

8. How closely does the mean acceleration compare to the values of g found in Steps 3 and 6?

List some reasons why your values for the ball’s acceleration may be different from the accepted value for g.

Conclusions: