Week 1 - Free Falling

all the files can be accessed by this link

the equation to calculate the height of an object in free fall is as follows

• h=(1/2)*g*t^2

where

g=acceleration due to gravity(m/s^2)

t=time(sec)

theory: A free-falling object is an object that is falling under the sole influence of gravity. Any object that is being acted upon only by the force of gravity is said to be in a state of free fall. Two important motion characteristics are true of free-falling objects:

• Free-falling objects do not encounter air resistance.
• All free-falling objects (on Earth) accelerate downwards at a rate of 9.8 m/s^2

1)

solution

step1: select motion view from the list

step2: setting up the units and gravity effect

ching units from "mm" to "m"

step3: select add body option

step4: assigning the mass and inertia values Izz, Ixx, and Iyy

step5: Check the use center of the mass coordinate system and select the origin point from unresolved to global origin. the center of mass is shifted to the global origin in the graphic window as shown.

step6: go to run solver panel, set the simulation time 2sec, save the model, and click Run.

wait for a few time so for the processor motion solve runs and provide the solution

step7: click on the plot and select the appropriate parameters to visualize the graph

the body is falling in a parabolic fashion with respect to time.

2)

no, the rate of fall of the free body is irrespective of its mass and inertial properties, any body suspended in free space will fall at the same acceleration rate

according to newton 2nd law

f=ma => mg

to prove, the properties of the body are changed has given data and graph is plotted

step8: change the mass properties has the following

• m=1kg (blue)
• m=10kg (red)
• m=100kg (green)

3) characteristics such as viscosity of the fluid, air resistance, drag, and buoyant force will affect the rate of fall

other properties which might be considered are

• surface area
• material density
• fluidity
• drag force

conclusion: the effect of mass and inertia on a body free-falling was understood and simulated in HyperWorks.