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Home Minds On Newton's Laws Mission NL10 Free Fall Acceleration Help Help 9

Mission NL10 Free Fall Acceleration

The Question

A 2-kg (or a 3-kg) object is free-falling from the top of a tall building. After 3 seconds (or 2 seconds) of free fall, its speed will be approximately ___ m/s and its distance of fall will be approximately ...

Think About It

An object that is in free fall is acted upon solely by the force of gravity. Such objects will accelerate at a rate of 9.8 m/s/s - approximately 10 m/s/s. That is, every second, the speed will change by approximately 10 m/s. Knowing the time of fall, allows one to quite easily determine the falling speed. If necessary, use the equations in the Formula Frenzy section.

Formula Fix

The final speed of an object after a certain time can be predicted using the kinematic equation:
 
vf = vo + a • t
 

The distance traveled by an object after a certain time can be predicted using the kinematic equation:
 
d = vo• t + 0.5 • a • t2

Define Help

Definition of Free Fall:
Free fall is the state of an object in which the only force acting upon it is the force of gravity.

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