Falling Stone

Problem: Find the displacement, velocity, and acceleration of a stone after one second, when the stone with zero initial velocity, falls under the influence of gravity. Note: If you need assistance on a step, just click on it for more information. Note: Click on images to enlarge.

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1) Click on Create a new model.

2) For the Model name change it to Falling_Stone.

3) For the Gravity choose Earth Normal (-Global Y).

4) For the Units, set it to MMKS - mm,kg,N,s,deg.

5) Then click OK.

1) From the ribbon Bodies select RigidBody: Sphere icon.

2) Put a check on Radius and set the radius to 5.0cm. Then click on the center of the working grid, to place the stone at <0,0,0>.

1) First right click on the Stone then choose Part:PART_2 and click Rename.

2) For the New Name type in Stone.

3) Choose Field Info and click Validate.

4) Click OK for Field validation was successful and click OK again.

1) Right-click the sphere, point to Part:Stone, and then select Modify.

2) Choose User Input on the drop down selection for Define Mass by.

3) Type 1.0 for the Mass and click OK.

1) Right-click on the Stone and choose Part:Stone and then click on Measure.

2) In the Measure Name text box enter Displacement, for the Characteristic select CM position, for the Component choose Y. Make sure that Create Strip Chart is checked then click OK.

3) A measure stripchart appears. It is empty because you need to run a simulation before Adams/View has the necessary information for the stripchart.

4) For more Measurements follow the instructions above and set Measure Name to Velocity and Acceleration, and Characteristic to CM velocity and CM acceleration.

1) In the right corner of the Status bar, right-click the Information tool stack, and then select the Verify tool.

2) In the Information window, check that the model has verified Successfully, then click Close.

1) Select the Zoom tool, and then click and drag the mouse to the zoom out until the entire working grid is visible.

2) Select the Translate tool, and then drag the working grid to the top of the screen.

3) In the Main Toolbox, select the Simulation tool.

4) In the End Time text box, enter 1.0 and in the Steps text box, enter 50.

5) Select the Play tool and when the simulation ends, reset the model by selecting the Reset tool.

1) To find the Stone's Displacement after 1 second, first right-click the blank area inside the stripchart, then choose Plot:scht1 then click on Transfer To Full Plot.

2) In Adams/Postprocessor, from the main toolbar, select the Plot Tracking tool.

3) Because you want to know the final conditions after 1 second, move the cursor over the end point of the plot. In the area below the menu bar, the value of X is displayed as 1. Note the value of Y is -4903.

  1. To find the disatance, use y = - (1/2) gt2
  2. Substitute: g = 9810 mm/s2 , t= 1 s, in the above equation.
  3. Results:
    • y = - 4905
  4. The results produced by Adams View is - 4903, this shows that the stone is traveling 4903 mm in the negative y direction. The hand calculated answer and the Adams/View generated answer has a 0.04% difference.