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Dec 15, 2008

Can you write a good final exam question?

As detailed in the post below, Problems 4 and 5 on the final exam will have five parts each with each part being a short calculation/short answer question. Over the weekend, I wrote the final exam. However, I have come up empty in my search for a good fifth part of Problem No. 5.

I have decided to turn this part of Problem No. 5 over to the class. I am asking that you submit a short calculation/short answer question for the exam. Please attach your submission as a comment to this post (I cannot accept email submissions as the entire class needs to see these questions prior to the exam). You do not need to write out the problem in complete detail; providing ideas is acceptable. However, the more details that you provide on the question the better. Please submit only questions -- do not provide answers. More than one submission is fine. I need to have all questions by 10AM on Saturday, December 13.

I am committed to including one of your submissions for this problem provided that more than three questions are submitted. In fact, if more than one submission looks good, I will replace some of my questions with yours.

I look forward to seeing your questions.

CMK


58 comments:

Brandon said...

What are Newton's 3 Laws in order?

Byron said...

How about the ranking of Io from smallest to greatest like the quiz question we had in class.

aschopra said...

Give a scenario and ask about the conservation of energy and momentum.

aschopra said...

Maybe you could give a few real life examples of vibrations and ask about what kind of response it will have.

gbaker said...

Ask a question about the velocity of a point on a disk.

Alex Taylor said...

Idea #1:

Give a schematic of a system with rotating rigid bodies and ask to find the Instant Center.

Mahdi Alhasan said...

A gun shhots a 6 g aluminum slug at 1/5 the speed of light. Assume a constant firing force acts to drive the slug through the 1.3 meter length of the barrel. Determine the work done on the slug during the firing of the gun

Johnny P said...

what is an orbit and how do orbits work

Spoons said...

Can the acceleration vector simply be determined as v_dot? Why or why not?

Derek said...

I think was mentioned in class a while ago but I don't remember using it. The example in our notes, on page 75 for work-energy equation for rigid bodes. Why does "T" in the example do no work?

RyanA said...

I was thinking maybe a situation based question. I'm quite the fan of roller coasters(plenty of dynamics there). Like maybe given that a car is going down a track at a certain velocity with a certain total weight(rider + ride vehicle) what is the angular velocity of its wheel? I think things along those lines are interesting.

812rbruins said...

What can be found by perpendicular bisecting two velocity vectors of a rigid body?

812rbruins said...

Why can the coefficient of restitution never be >1 ?

812rbruins said...

With only one frame of reference, can static friction do work? Explain.

wccheng said...

give real life examples of the coriolis effect

wccheng said...

T and F of Instant Centers:
1) Great way to visualize motion?
2) Great way to solve problems?
3) a_ic=0?
4) Method works for solving accel. problems?
5) Vel. of contact point = 0 for no slip?
6) Accel. of contact point = 0 for no slip?
7) w=0 => alpha = 0 ?

Johnny P said...

why are rate change of speed and acceleration not the same?

garrettmocas said...

Give us a serious of FBD's, one correct and several incorrect for the same system, and have us find the mistakes and/or choose the correct one.

Unknown said...

A question having to do with the fact that the acceleration of the contact point on a wheel is all in the perpendicular plane only if it is a non slip surface.

Unknown said...

Give us a more challenging Newton Euler Equations and have us find the EOM.

Byron said...

Let's think simple. Spell the Professor's last name?

Soetjiandi,Steven said...

You have 2 Battery, one is the small AAA, the other one is the medium AA, You rolled both of them at the same time from the top of a ramp, which one will reach the bottom of the ramp faster? why? Is it dependent to the mass?

or

A hollow ring and a solid ring rolled from the top of the ramp, which one will reach the bottom of the ramp faster? Why?

jjj said...

Potenial questions:
What is today's date?
What day in super bowl sunday?
What time is it (roughly)?
What is the web address for the blog's homepage?



Simple isn't bad people.. remember that.

Alex Taylor said...

For people who came to class:

What SciFi movie was referenced during the lecture about angular velocity and artificial gravity?

Anonymous said...

How about if you have an old-fashioned toaster oven with a spring that causes the toast to pop up when it's done. Suppose when you push the lever down, it applies a certain potential energy to the spring that holds the slice of toast down, and the toast pops up a certain amount when the spring is released. Given the mass and dimensions of the toast, and the distance the spring is stretched (and of course the applied force), we could calculate the energy transferred to the toast, and subsequently how high the toast "jumps" off the platform it rests on when the spring pops back to its un-stretched length and stops moving. (Sound too complicated? I think it might be interesting!)

cynric said...

How about a problem where we are given a number of forces acting on an object, then we have to set up the correct FBD.

Jacob.Oswalt said...

True or False: V_dot is equal to Acceleration.

CMK said...

You guys have put together an impressive list of questions up to this point.
* I have chosen one question submitted as part e) of Problem No. 5.
* I chose another question to replace one of the problems that I wrote.
* Questions posed by the following people are covered in some way by other questions already on the exam: Alex Taylor, Spoons, Derek, 812rbruins, wccheng, Johnny P and Jacob Oswalt.

Please continue to submit questions up until 10AM on Saturday. I can still replace more of my questions with yours.

Good job!

Spoons said...

Why does friction at a no slip contact point for a rotating disk equal 0?

Spoons said...

Give some examples of different systems and ask whether they are better modeled as a rigid body or a particle.

CMK said...

--to Spoons--
Please note that the friction force required for no slip is NOT zero. However, the work done by the friction force is zero. This is probably what you meant to say.

Spoons said...

Two hoops of equal mass roll down an incline with no slip. One of the hoops is an empty ring while the other has four spokes. Will one of the hoops be moving faster at the end of the run? If so which one?

J.T. Kinsey said...

I would like to know how many people remember some key topics from the fundamentals exam that we took the second week of school! I know we had the fundamentals exam and a quiz over it, but I think asking a question about the chain rule and projection should be fair game! We won't have any excuses for missing that!

Phil B said...

Explain why we can neglect the force due to gravity in most problems involving resonance and free response.

Anonymous said...

Going way back to rigid body kinematics... Given a simple mechanism, show how you can determine the angular acceleration of a link using the instant center method and using just the vector approach.

jmsimpso said...

What about a question to state the two key steps to the derivation of the work energy equation for a particle from Newton's second law? It was on a quiz I think.

jmsimpso said...

Or a problem about two object coming in contact with each other and finding the coefficient of restitution.

aschopra said...

Why would a ride on an empty truck(not carrying any load) be uncomfortable for a passanger.

aschopra said...

What kind of a spring constant (small or large) would a luxury car have compared with a pickup truck of the same mass. justify your answer.

Byron said...

1) Draw the typical Forced response (w/wn) vs Amplitude graph

2) Would would you feel the curvature of a sinusodial road more if you A) Drive faster B) Drive Slower C) Add more weight to the car D) Reduce the weight of the car E) Use stiffer springs F) Use softer springs

Circle all that Apply.

Steve-o said...

What direction to atmospheric currents follow in the Northern hemisphere compared to currents in the Southern hemisphere? Justify your answer.

Fady said...

When taking a turn in a car, why do we feel a force pushing us away from the center of rotation, while we always say that the force is supposed to always act towards the center of rotation?

Fady said...

Given a car, moving with a speed v, that is approaching a downward incline of a certain angle theta. Determine the minimum speed v such that the car 'flies' over for some time before landing back on the ground.

jcleaver said...

What is the formula for the coefficient of restitution?

jcleaver said...

Can the rate of change of speed and the magnitude of acceleration ever be the same? Why or why not?

jcleaver said...

Is there truely such a thing as centripetal force?

rpmccaul said...

Before making a trip over Lindberg Road, I have 10 cement blocks in the bed of truck, should I put 10 more blocks in or take 10 out in order to make for a "smoother" ride?

rpmccaul said...

In what year what Purdue University originally established?

rpmccaul said...

What is CMK's first name?

Robert Charles said...

If a Football is flying through the air with an omega and a flee is flapping its wings as it walks along the ball... what is the speed of its wings at a given time?

M Sandercock said...

How about another IC problem, where you have to locate the IC of a system and identify which direction one member is rotating?

M Sandercock said...

A situation where you have 2 boxes on a horizontal surface connected by a single system of pulleys (i.e. La=3ya+5yb+C) and determine the relationship between the v of each.

Robert Charles said...

Label an FBD with all forces then explain which forces do work and which ones don't and which forces are conservative and which ones aren't. We had a quiz just like this.

Alex Taylor said...

Did I hear you correctly in class, each question postulated here is worth 40 points towards blog participation?

Vincent Lingle-Munos said...

Explain how an olympic shooter might take into account the coriolis effect on a day with strong winds.

Bonus: Explain how an archer might take this into account on a similar day.

Vincent Lingle-Munos said...
This comment has been removed by the author.
Vincent Lingle-Munos said...

A disk of mass m rests on top of a circle of radius R, its center connected to a spring (with spring constant k) that has a constant stretch of delta (the triangle symbol) pinned to the center of the circle.

The disk is given an initial angular velocity w(o).

Neglecting Friction, determine the minimum spring constant k in terms of m, g, R, and delta so that the disk can complete a revolution while staying in contact with the circle.

GeunHo Choi said...

Find velocity of two objects that are connected by an unstretchable wire. Adding pulleys in the drawing might make the problem more exciting