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06-28-2014, 06:46 PM   #9181
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Zombies!!!!!!!!! Well that does it for me. I have been trying to decide between a K3 and a shotgun. I guess I need to get the shotgun to defend against Zombies.

06-28-2014, 09:20 PM - 1 Like   #9182
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QuoteOriginally posted by Racer X 69 Quote
No offense taken.

But.

Will a 645Z hit 150mph + on the straights?
wellll, let's see
Terminal velocity = Sqrt((2 * mass * g) / (air density * projected area * drag coeff))
Mass = 1.5kg (w/ batteries)
g =9.8
air density at +25*C (there's no point to experiment in the cold) - about 1.18kg/m3, humidity and change of t* depending on height are not taken into account

dimensions: 0.156 * 0.117 * 0.123m
for our purposes, let's round it to cube: .125 x .125 x .125
technically, the projected area changes all the time (rotation during the fall), but for our scientific purposes, let's assume, that it is falling down with one edge pointing downwards, so we have 2 sides projected at 45 degree angle.
Formula is: L x H * cos(angle) = .125*.125*cos(45) * 2 (since 2 sides are projected) = 0.022 m2 (cos(45) = .71)
drag coefficient for a cube is 0.8 (wiki it)

so, the result:
terminal velocity in air for 645Z = sqrt((2*1.5*9.8) / (1.18 * .022 * .8)) = 37.62m/s = 135.4km/h = 84.2mph

No. 645z can't do 150mph
06-29-2014, 02:59 AM   #9183
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QuoteOriginally posted by karro Quote
No. 645z can't do 150mph
Of course a 645Z can do 150mph. It just needs to be propelled by sufficient force. Much like the Datsun, really. Or the early stages of bacon - they really can fly.

Ok, the 645Z might not travel in a straight (horizontal) line. Ballistics are rarely linear.
06-29-2014, 03:17 AM   #9184
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QuoteOriginally posted by gaweidert Quote
Zombies!!!!!!!!! Well that does it for me. I have been trying to decide between a K3 and a shotgun. I guess I need to get the shotgun to defend against Zombies.
Yep ... a 12 gauge automatic might be best ... too tiring to pump each time.

And while shooting, do NOT forget to play "Who's Next" as loud R&R back ground music !!!



06-29-2014, 03:40 AM   #9185
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QuoteOriginally posted by Jean Poitiers Quote
Yep ... a 12 gauge automatic might be best ... too tiring to pump each time.
Nah, give me a proper catapult and a good supply of K-3s. I'm certain they would be more lethal to zombies (too) than a puny 12 gauge.

But "Who's next" is a good choice.
06-29-2014, 03:43 AM   #9186
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Oh, just realised I stumbled upon a reason for getting a K-3. Rats.

Well, not literally rats. Zombies. But... Rats.
06-29-2014, 12:04 PM   #9187
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Being bored one day, I actually read through the TOS for an online service that we use at work. It was -- surprise! -- a serious yawn-inducing document until I got to the part about their not being responsible for stuff like acts of God, war and the like. The list actually included "Zombie Apocalypse" as one of the events. I am not making this up!

Probably they will have to amend it to include Invasion of the hociR...
06-29-2014, 12:42 PM   #9188
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QuoteOriginally posted by OrchidJulie Quote
Being bored one day, I actually read through the TOS for an online service that we use at work. It was -- surprise! -- a serious yawn-inducing document until I got to the part about their not being responsible for stuff like acts of God, war and the like. The list actually included "Zombie Apocalypse" as one of the events. I am not making this up!

Probably they will have to amend it to include Invasion of the hociR...
It's already happening here ... micro Zombie Apocalypses!

Next one should start happening tomorrow at 18h00 Paris time ... game time.

Beat in the head of a Zombie with a K-3 will only render it more powerful ... France & Tokyo are dooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooomed!

(Kinda of like "Goooooooooooooooooooooooooooooooooooooooooooal!" there, n'est-ce pas?! )

06-29-2014, 12:48 PM   #9189
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Here? Non. The "goooooooooooooooal!" announcer is somewhere in Latin America.

Wait,. Miami is somewhere in Latin America.... we're doomed, too...
06-29-2014, 05:23 PM   #9190
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QuoteOriginally posted by monochrome Quote
I owned a K50/1.2 for about a year. I rarely used it wider than f/5.6 but focusing the bright image was great. Of course focusing the bright image of my K50/1.4 was also great. And I rarely use it wider than f/5.6 either. I don't miss the stop and enjoy the $575.

I guess I am benighted.
I love the view in my LX with the 50/1.2 is on board and the SA-23 screen in the viewfinder. If you have never experienced it you have not truly lived. And the photos ain't bad either.
06-29-2014, 05:35 PM   #9191
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QuoteOriginally posted by Pioneer Quote
I love the view in my LX with the 50/1.2 is on board and the SA-23 screen in the viewfinder. If you have never experienced it you have not truly lived. And the photos ain't bad either.
No doubt. I think about few lenses I've sold. Vivitar 105/2.65 Macro very often. Pristine K135/2.5 with case and hood whenever I use the second copy I bought. K50/1.2 - I know I had it once. That's enough.
06-29-2014, 05:39 PM   #9192
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QuoteOriginally posted by monochrome Quote
No doubt. I think about few lenses I've sold. Vivitar 105/2.65 Macro very often. Pristine K135/2.5 with case and hood whenever I use the second copy I bought. K50/1.2 - I know I had it once. That's enough.
I do enjoy my Vivitar 105 Macro. It has replace my other macro lenses with the exception of the 90-180 Vivitar flat field zoom.

I gave up selling lenses, that way there is no regret.
06-29-2014, 05:45 PM   #9193
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You guys are taking lenses? That's dangerously close to being on topic... you guys like living ion the edge.
06-29-2014, 06:35 PM   #9194
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QuoteOriginally posted by gaweidert Quote
Zombies!!!!!!!!! Well that does it for me. I have been trying to decide between a K3 and a shotgun. I guess I need to get the shotgun to defend against Zombies.
QuoteOriginally posted by Jean Poitiers Quote
Yep ... a 12 gauge automatic might be best ... too tiring to pump each time.

And while shooting, do NOT forget to play "Who's Next" as loud R&R back ground music !!!
QuoteOriginally posted by savoche Quote
Nah, give me a proper catapult and a good supply of K-3s. I'm certain they would be more lethal to zombies (too) than a puny 12 gauge.

But "Who's next" is a good choice.
QuoteOriginally posted by OrchidJulie Quote
Being bored one day, I actually read through the TOS for an online service that we use at work. It was -- surprise! -- a serious yawn-inducing document until I got to the part about their not being responsible for stuff like acts of God, war and the like. The list actually included "Zombie Apocalypse" as one of the events. I am not making this up!

Probably they will have to amend it to include Invasion of the hociR...
QuoteOriginally posted by Jean Poitiers Quote
It's already happening here ... micro Zombie Apocalypses!

Next one should start happening tomorrow at 18h00 Paris time ... game time.

Beat in the head of a Zombie with a K-3 will only render it more powerful ... France & Tokyo are dooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooomed!

(Kinda of like "Goooooooooooooooooooooooooooooooooooooooooooal!" there, n'est-ce pas?! )
Now you all really need a couple of these for the Zombie Apocalypse.

06-29-2014, 06:51 PM   #9195
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QuoteOriginally posted by karro Quote
wellll, let's see
Terminal velocity = Sqrt((2 * mass * g) / (air density * projected area * drag coeff))
Mass = 1.5kg (w/ batteries)
g =9.8
air density at +25*C (there's no point to experiment in the cold) - about 1.18kg/m3, humidity and change of t* depending on height are not taken into account

dimensions: 0.156 * 0.117 * 0.123m
for our purposes, let's round it to cube: .125 x .125 x .125
technically, the projected area changes all the time (rotation during the fall), but for our scientific purposes, let's assume, that it is falling down with one edge pointing downwards, so we have 2 sides projected at 45 degree angle.
Formula is: L x H * cos(angle) = .125*.125*cos(45) * 2 (since 2 sides are projected) = 0.022 m2 (cos(45) = .71)
drag coefficient for a cube is 0.8 (wiki it)

so, the result:
terminal velocity in air for 645Z = sqrt((2*1.5*9.8) / (1.18 * .022 * .8)) = 37.62m/s = 135.4km/h = 84.2mph

No. 645z can't do 150mph
I see.

Very nice explanation too!
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