3.09 Fictional Physics - 2nd Law

Name:

The Scenario

The villain (pick your favorite) has just dropped an innocent bystander from this very tall building in order to distract the hero (pick your favorite) and make a getaway. The building is high enough for a person to reach terminal velocity. 

With just one story to go our hero swoops in and catches the bystander and sets (him or her) down onto the sidewalk perfectly at rest.

How much force would it take to bring the bystander to a rest over that distance, and would the bystander be able to survive that?

Step 1 - Draw A Picture

Make sure to label everything that seems important. Make one informal picture and then off to the side draw a free body diagram of the bystander that represents the forces present while the hero is bringing him or her to a stop.

Step 2 - Knowns and Unknowns

Below is a list of information that you will need to look up or make an assumption about in order to solve the problem. Reference/cite all information you look up, justify all information that you are making assumptions about.

Bystander Mass (kg):

Height of one story (m):

Person’s Terminal Velocity (m/s):

Watch this video: How Does Terminal Velocity Work? 

Give a definition for what terminal velocity means:

Your unknown is (unit?):

Step 3 - Equations

List out the equations that you think will help you solve this problem. Your equations will introduce some new unknowns that should cancel out when you are working through step 4.

Step 4 - Solve Symbolically First

Rearrange the equations you listed in step 3 to come up with one equation that will give you the answer that you are looking for, and then plug in the known quantities and find your unknown.

Step 5 - Check Your Answer

What was the acceleration?

What was the force used?

Explain what g-force is:

Calculate how many g’s the person would be decelerated at:

Does this seem reasonable? What are you basing this on? Is it survivable?

Grading Rubric

Section	Poor	Fair	Excellent
DAP ___5pts	Picture depicts only some of the aspects of the problem.	Picture depicts most aspects of the problem	Picture clearly depicts all aspects of the problem
KNU ___5pts	List contains some information.	List contains most information.	List contains all information.
EQN ___5pts	Some of the equations are listed.	Most equations are listed.	All equations that could be needed are listed.
SSF ___5pts	Student made major errors in solving for the unknown.	The student made minor mistakes or didn’t solve all symbolically first.	The student correctly solved for the unknown.
CYA ___5pts	Reasoning does not fit or is absent.	Student is a little bit unclear on reasoning.	Student gave sound reasoning for their perceived correctness