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LWW
03-25-2011, 11:33 AM
No googling.

A remote controlled car is traveling in a straight line at a constant speed of 60 MPH on a glass smooth road.

What is the net force on the vehicle.

LWW
03-25-2011, 11:38 AM
Question #2:

I am free floating in space in a space suit.

I see woofie pass me at 60 MPH.

Is the correct answer:

A - Woofie is actually going 60 MPH.

B - LWW is actually going 60 MPH.

C- We are both going 60 MPH?

D - None of the above.

E - All of the above.

pooltchr
03-25-2011, 11:41 AM
Not enough information to make that determination.

There are many forces acting on the car. Weight of the car would figure in on the gravitational force. size and shape would be factors in the amount of wind resistance. The energy used to rotate the wheels would be another force being applied to the car.

I'm sure there are others I haven't even thought about.

Steve

LWW
03-25-2011, 11:50 AM
Sorry, but you are wrong.

This is basic Newtonian physics. Think of Newton's three basic laws.

LWW
03-25-2011, 11:59 AM
Question #3:

Inside a 5 mile long shooting range I shoot a bullet that has enough gunpowder to propel the bullet 4.9 miles forward.

The building is a vacuum and the gun is positioned so that the bullet is fired perfectly level with the perfectly flat floor.

A second bullet is held at the exact same height as the other bullet when it leaves the barrel.

One bullet leaves the barrel at the exact moment the second bullet is dropped.

Will:

- The fired bullet hit the floor first.

- The dropped bullet hit the floor first.

- Neither of the above answers is correct.

LWW
03-25-2011, 12:26 PM
Besides, by using the word "KNOW" I was hoping our resident leftist science admirers could show me how much they really knew.

Any one else can PM me with an answer and I'll tell you if it's right, or post it here ... either one.

Anyone who just wants the answers can PM me also.

Soflasnapper
03-25-2011, 12:39 PM
Since F = MA, no acceleration, no force.

Can't you come up with something better than high school physics 101?

Soflasnapper
03-25-2011, 12:41 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">Question #2:

I am free floating in space in a space suit.

I see woofie pass me at 60 MPH.

Is the correct answer:

A - Woofie is actually going 60 MPH.

B - LWW is actually going 60 MPH.

C- We are both going 60 MPH?

D - None of the above.

E - All of the above. </div></div>

D.

Soflasnapper
03-25-2011, 12:42 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">Question #3:

Inside a 5 mile long shooting range I shoot a bullet that has enough gunpowder to propel the bullet 4.9 miles forward.

The building is a vacuum and the gun is positioned so that the bullet is fired perfectly level with the perfectly flat floor.

A second bullet is held at the exact same height as the other bullet when it leaves the barrel.

One bullet leaves the barrel at the exact moment the second bullet is dropped.

Will:

- The fired bullet hit the floor first.

- The dropped bullet hit the floor first.

- Neither of the above answers is correct. </div></div>

Neither

pooltchr
03-25-2011, 12:44 PM
I took physics in college as a required course, but never really studied it in depth.
In recent years, I have studied physics as it applies to the game of pool, since it is something I need a good understanding of in order to teach others. I understand what happens when two spheres collide, and how each will react, how energy is transfered from one object to another, how energy can be developed in directional or rotational speed.
Beyond that area of physics, I claim no more than a general knowledge of the subject.

Steve

LWW
03-25-2011, 12:44 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Soflasnapper</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">Question #2:

I am free floating in space in a space suit.

I see woofie pass me at 60 MPH.

Is the correct answer:

A - Woofie is actually going 60 MPH.

B - LWW is actually going 60 MPH.

C- We are both going 60 MPH?

D - None of the above.

E - All of the above. </div></div>

D. </div></div>

Close. What is your reason for that answer?

LWW
03-25-2011, 12:45 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Soflasnapper</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">Question #3:

Inside a 5 mile long shooting range I shoot a bullet that has enough gunpowder to propel the bullet 4.9 miles forward.

The building is a vacuum and the gun is positioned so that the bullet is fired perfectly level with the perfectly flat floor.

A second bullet is held at the exact same height as the other bullet when it leaves the barrel.

One bullet leaves the barrel at the exact moment the second bullet is dropped.

Will:

- The fired bullet hit the floor first.

- The dropped bullet hit the floor first.

- Neither of the above answers is correct. </div></div>

Neither </div></div>

Correct.

The firing force only propels the one bullet forward.

Both bullets are affected by gravity identically, so they would hit the floor at the same moment.

Soflasnapper
03-25-2011, 01:18 PM
The theory of special relativity. Depending upon what fixed frame of reference is used, it could be true that you are doing 60, he is doing 60, or you're both doing 30. Since there is no fixed frame of reference, and all of these could be (relatively) true, none of them is (absolutely) true.

LWW
03-25-2011, 04:13 PM
You actually have it then, as I suspected.

Put another way however, all of them are true.

Most people believe relativity to be far more complicated than it is.

As you know, all it means essentially is that speed can only be measured as relative to something else.

As I drive 100MPH down the freeway, that figure is relative to my observed as stationary surroundings. An equally valid point could be made that I am going several hundred miles per hour as the Earth is rotating ... or that I'm going much faster as I'm orbiting the Sun at tremendous speed ... or that I'm doing 35 MPH as I pass the luddite in the fast lane with their blinker on.

LWW
03-25-2011, 04:18 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">No googling.

A remote controlled car is traveling in a straight line at a constant speed of 60 MPH on a glass smooth road.

What is the net force on the vehicle. </div></div>

Nobody has this one yet?

And our resident high priestess of science is surprisingly not feeding woofie the answers?

cushioncrawler
03-25-2011, 04:34 PM
Straight, 60mph, (metal) car, on a road, on earth, in air.

(Force 1) The forward force of the wheels (on the road) would equal (Force 2) the air drag (slowing the car).

(Force 3) There would be an upward force on the wheels equalling the down force.

(Force 4) There would be aerodynamik forces and torques akting on the car akting down & up or whatever (mainly up) -- apart from what we call gravity (Force 5). We shood inklood the aerodynamik forces relating to sucking air into the engine and spitting it out (the back), and the radiator fan (thrust) too.

(Force 6) If mooving in a straight line then there would be say 3 Coriolis type forces and 3 torques akting on the car due to the spin and curvature of the earth.

(Force 7) There would be electrical or magnetik forces akting on the car due to the metal etc kutting the earth's etc magnetik field. Theze probly retard the car, might be some lift etc. Shood inklood ditto for electric currents in the wiring, and the statik electicity on/in the car.

(Force 8) I guess that we kan ignore internal torq of engine and wheels and any thing rotating in a steady fashion. Alltho the remote kontrol worrys me -- this might rezult in some nett external forces and torqs of some sort from time to time. If the car woz deskribing some sort of curved path or if it were turning (yawing etc) then the rotational momentum and rotational inertia of thems spinning turning things would rezult in external forces, but they dont/wont here koz the car iz going in a straight line (ie straight in 3 dimensions).

(Force 9) We can ignore exotik kurved space-time Einsteinian etc stuff koz that stuff iz all bullshit, and in any case mostly duznt raise its ugly head if the car iz travelling straight at uniform speed etc.
Alltho it would be diffikult to define what sort of "straight" we are talking about. Straight to who. Who iz the observer??

(Force 10) If the car iz going along the equator then thats ok. But if not then the car (thrust) forces will cause the earth's rotation to change direktion. This will (might) require some (remote) steerage (depending on what iz straight and what iznt). Steerage will need steering forces on the wheels (ie on the road). Steering forces will then bring rotational inertia of the wheels into play (Force 11), rezulting in more torq etc on the car, plus some on the earth, which will breed more Force 10,etc etc etc.
mac.

LWW
03-25-2011, 04:36 PM
And the net force would be?

cushioncrawler
03-25-2011, 04:41 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">Question #2:I am free floating in space in a space suit.I see woofie pass me at 60 MPH. Is the correct answer:A - Woofie is actually going 60 MPH.B - LWW is actually going 60 MPH.C- We are both going 60 MPH?D - None of the above.E - All of the above.</div></div>A haztabe korrekt.
mac.

cushioncrawler
03-25-2011, 05:04 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">Question #3:Inside a 5 mile long shooting range I shoot a bullet that has enough gunpowder to propel the bullet 4.9 miles forward.The building is a vacuum and the gun is positioned so that the bullet is fired perfectly level with the perfectly flat floor.A second bullet is held at the exact same height as the other bullet when it leaves the barrel.One bullet leaves the barrel at the exact moment the second bullet is dropped.Will:- The fired bullet hit the floor first.- The dropped bullet hit the floor first.- Neither of the above answers is correct.</div></div>I think it depends on which way the gun points in relation to the earth's rotation. The fired bullet can hit first, or not, or they hit at same time, depending on whether pointing east or west or ????.
mac.

Soflasnapper
03-25-2011, 05:18 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">No googling.

A remote controlled car is traveling in a straight line at a constant speed of 60 MPH on a glass smooth road.

What is the net force on the vehicle. </div></div>

Nobody has this one yet?

And our resident high priestess of science is surprisingly not feeding woofie the answers? </div></div>

I answered this as the 7th post, page 1, which see.

cushioncrawler
03-25-2011, 05:30 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">And the net force would be?</div></div>Hmmmm -- i suppoze that the nett force must be zero -- allmost.

Exept for the Coriolis stuff that i mentioned. Coriolis effekts are not forces or torqs. They exist due to the kar's internal inertia. Hencely the forces and torqs needed to keep the kar going straight (ie rezisting Coriolis) are nett forces.

Perhaps Coriolis wouldnt raise hiz ugly head if u were driving along the equator.
mac.

cushioncrawler
03-25-2011, 06:06 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">No googling. A remote controlled car is traveling in a straight line at a constant speed of 60 MPH on a glass smooth road. What is the net force on the vehicle.</div></div>glass smooth road.
When i saw this i naturally woz alert to the fakt that most pipple uze this sort of wordage (wrongly) when meaning that there woz zero friktion. Being glassy or smooth duznt mean zero friktion.
Then i thort that perhaps it meant that rolling rezistance woz zero or at least very low.
Why would friktion and rolling rezistance affekt the answer.

Calling it a road implyed that the question woz meant to be fairly basik, not too theoretikal -- probly needing a skoolkid type answer.

remote controlled.
I wondered why remote controlled. This too seemed to hav (allmost) zero effekt on any answer. How kood a driver in the car make a difference???

car -- vehicle.
Why call it a car & later a vehicle??

nett force on the vehicle.
A force akting on the car might be different to a force having its origin in the car. Kood be a trap. Az it turns out Coriolis iz indeed in the driver's seat.
mac.

I shood point out that i woz a Traffik Engineer -- so i know a bit about cars and roads.
mac.

cushioncrawler
03-25-2011, 06:29 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">Question #2: I am free floating in space in a space suit. I see woofie pass me at 60 MPH. Is the correct answer:
A - Woofie is actually going 60 MPH.
B - LWW is actually going 60 MPH.
C- We are both going 60 MPH?
D - None of the above.
E - All of the above.</div></div>I must change my mind and go for E.
But here i havta ignore that all of the above inkloods D. I guess it woznt meant to inklood D.
mac.

Soflasnapper
03-25-2011, 06:35 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cushioncrawler</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">And the net force would be?</div></div>Hmmmm -- i suppoze that the nett force must be zero -- allmost.

Exept for the Coriolis stuff that i mentioned. Coriolis effekts are not forces or torqs. They exist due to the kar's internal inertia. Hencely the forces and torqs needed to keep the kar going straight (ie rezisting Coriolis) are nett forces.

Perhaps Coriolis wouldnt raise hiz ugly head if u were driving along the equator.
mac. </div></div>

That force is so de minimis that it's a 5th order of magnitude lower at least, and essentially zero.

But you are right before to list all the forces involved, although they are all off-setting so the net is zero, as was said by me.

cushioncrawler
03-25-2011, 06:42 PM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">Question #3:Inside a 5 mile long shooting range I shoot a bullet that has enough gunpowder to propel the bullet 4.9 miles forward. The building is a vacuum and the gun is positioned so that the bullet is fired perfectly level with the perfectly flat floor. A second bullet is held at the exact same height as the other bullet when it leaves the barrel. One bullet leaves the barrel at the exact moment the second bullet is dropped. Will:
- The fired bullet hit the floor first.
- The dropped bullet hit the floor first.
- Neither of the above answers is correct.</div></div>Thinx.
perfectly flat floor.
A flat floor kood be 2 or 3 feet higher or lower at one end than the other, depending on which bit woz horizontal.
A non-flat floor can be horizontal all the way.
None of this matters.

fired perfectly level with.
This means that the bullet iz fired parallel with the floor. Not necessaryly horizontally.
Parallel iz ok.

Anyhow, the winning bullet would allmost certainly depend on the direktion of the range, north south east west.
Shooting East -- Dropped bullet wins. And fired bullet iz disqualyfyd anyhow for hitting the southern wall before hitting the floor.
Shooting West -- Dropped bullet loozes, but wins koz fired bullet iz disqualyfyd for hitting the northern wall before hitting the floor.
Shooting North -- The fired bullet would ricochet off the eastern wall. The dropped bullet would ricochet off the western wall. The judges are still examining the slo-mo to see which one ricocheted first and hence be disqualyfyd. But the slo-mo would show both hitting floor at same time anyhow. Aktually, they wouldnt hit the floor at the same time, i just then thort of something.
Shooting South -- Same deal az shooting North except that the dropped bullet ricochets off the other wall, and likewize the fired bullet.

This assumes side walls are vertical. But in fakt vertical walls wont get around that little thing i just thort of. Praps more later.
mac.

JohnnyD
03-26-2011, 01:03 AM
Shoot the bullet straight and it will go.

LWW
03-26-2011, 03:52 AM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Soflasnapper</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">No googling.

A remote controlled car is traveling in a straight line at a constant speed of 60 MPH on a glass smooth road.

What is the net force on the vehicle. </div></div>

Nobody has this one yet?

And our resident high priestess of science is surprisingly not feeding woofie the answers? </div></div>

I answered this as the 7th post, page 1, which see.

</div></div>

My apologies, I missed it completely ... yes, you do have it correct.

It seems that the self proclaimed high priestess of science and her minions have no actual knowledge of science whatsoever?

LWW
03-26-2011, 03:56 AM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cushioncrawler</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">Question #2: I am free floating in space in a space suit. I see woofie pass me at 60 MPH. Is the correct answer:
A - Woofie is actually going 60 MPH.
B - LWW is actually going 60 MPH.
C- We are both going 60 MPH?
D - None of the above.
E - All of the above.</div></div>I must change my mind and go for E.
But here i havta ignore that all of the above inkloods D. I guess it woznt meant to inklood D.
mac. </div></div>

Actually it was meant to include D.

IT depends entirely upon what speed is being measured relative to, which was undefined.

If it was defined as relative to woofie, then woofie would be traveling 60 MPH and I would be stationary. From woofie's POV he would be stopped and I would be traveling 60 MPH relative to him.

Qtec
03-26-2011, 04:49 AM
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Soflasnapper</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LWW</div><div class="ubbcode-body">No googling.

A remote controlled car is traveling in a straight line at a constant speed of 60 MPH on a glass smooth road.

What is the net force on the vehicle. </div></div>

Nobody has this one yet?

And our resident high priestess of science is surprisingly not feeding woofie the answers? </div></div>

I answered this as the 7th post, page 1, which see.

</div></div>

My apologies, I missed it completely ... yes, you do have it correct.

It seems that the self proclaimed high priestess of science and her minions <u>have no actual knowledge of science whatsoever?</u> </div></div>

LMAO...much like you...as sofla has so excellently pointed out.

Sofla is 10 times smarter than you are but you just too dumb to see it.

Q.......LMFAO

LWW
03-26-2011, 04:55 AM
Nice of you to come out once the answers are posted Snoopster.

That being said, we both know that you don't understand the answers even when given.

As to whether or not sofla has a higher IQ ... I don't know and don't really care. The only given is that in a three way IQ contest ... you would pull in to last place, and by a comfortable margin.

I am replying to you directly this time only because you decided to make a personal comment after hiding the entire time the questions were debated.

LWW
03-26-2011, 05:53 AM
Question #4:

If one constructed a closed room insulated so well that it allowed zero heat transfer in or out, and then remotely turned on a ceiling fan the result would be:

A - The room temp would slowly fall.

B - The room temp would slowly rise.

C - The room temp would remain constant.

D -Insufficient data.

cushioncrawler
03-26-2011, 06:18 AM
B - The upwards force on the room would be reduced in the first few seconds, and then the upwards force would slowly return to its original size.
The room would then bulge out, due to the pressure inside due to the hi temp due to the room burning due to the hi temp due to the fan.
Then when the fan failed the upwards force on the room would inkreec to more than its original size, before it slowly returned to original.
The bulging would inkreec further due to the burning.
Then the burning would stop due to lack of oxygen, but the bulging would stay az iz forever, due to the trapped heat and trapped everything.
Unless electricity continued to flow to the kaput fan, in which case there would be (allmost) no limit to the temp rize if the room held together ok.
mac.

LWW
03-26-2011, 06:43 AM
You are an interesting guy Mac.

LWW
03-26-2011, 03:43 PM
I forgot to mention ... you are right, although not for the reasons you stated.

cushioncrawler
03-26-2011, 04:00 PM
I hav dunn experiments with fans and cardboard boxes, so i am a world authority on fans and cardboard boxes.
A ceiling fan in a closed box kan hav lift for sure.

But it would be better science if u replaced the ceiling fan with a light globe. Koz then u would get global warming.
mac.

LWW
03-27-2011, 05:11 AM
Question #5:

A man gets on a motorcycle with a perfectly functioning speedometer.

He circles a mile oval track 12 times in 12 minutes.

The average velocity of the bike and rider was:

A - 60 MPH.

B - 12 MPH.

C - Something else.

Give your answer and explain how you arrived at the answer.

cushioncrawler
03-27-2011, 05:04 PM
Are u sure it woz a man???
How kan he circle an oval track???
A speedometer measures speed in meters per second -- it wouldnt work on a mile track.
How did the motorcycle bekum a bike???
We can calculate the ave velocity of the bike, and even the rider, but bike and rider duznt compute.

They went 12 miles in 12 minutes, and then we kan only assume that they didnt moov for 48 minutes.
Hencely the ave speed woz 12 MPH.

However, we dont know which way, clockwize or anticlockwize.
Lap 1 might hav been CW, and Lap 2 ACW, etc etc.

Kleerly someone woz watching. If it woz the rider talking he would hav sayd "i" got on, and "i" circled, and "my" ave vel woz.
So we hav an independant observer. That observer woz probly in the center of the track. But he/she might hav been on the bike sitting behind the (other) rider.

If she woz a she, she woz probly a biker's mole. If so, then the biker woz probly a member of a bikie gang. If so, then they were probly dizzy on drugs.
If they koodnt go more than 12 minutes without having another hit of something, it woz probly weed. A joint would take about 12 minutes if shared.
Ok, now we are getting somewhere. Did this bike hav an ashtray???
I need to know koz that kood komplikate the answer.
mac.

LWW
03-29-2011, 04:58 AM
Where are the great scientific minds of the cabal?