Problem 1: Dynamic Analysis of a Free-falling Rigid Body

Objective

A ball is tossed with a velocity of 10 m/s directed vertically upward from a window located 20 m above the ground. The acceleration of the ball is constant and equal to 9.81 m/s2 downward. The objective is to determine the highest elevation reached by the ball and the corresponding time.



Figure 1.

Entities Validated

  • Rigid body
  • Acceleration due to gravity

Type of Analysis

  • Dynamic

Reference

Vector Mechanics for Engineers: Statics | Dynamics, Twelfth Edition by Beer, Johnston, Mazurek, Cornwell, Self : 624,625

Model Files

  • ball_position.mdl - MotionView Model
  • ball_position.xml - MotionSolve Deck

Graphical Results



Figure 2.

Result Comparison

Output Analytical MotionSolve % Error
Highest elevation (m/s) 25.1 25.1 0%
Time at Highest elevation (s) 1.02 1.02 0%

Conclusion

MotionSolve results compare well with the analytical results.