Convict on 31/1/2007 at 11:50
Is that a trick question? Assuming we don't take into account the resistant force due to friction then all the opposing force is vertical but I assume all the force from the wind is horizontal.
Therefore the skylight will blow off sideways with any non-zero velocity.
Briareos H on 31/1/2007 at 12:07
velocity = sqrt ( 2 ( pressure_std - ( 500N + mass_window * gravity_acceleration ) / area_window ) / density_air )
lol
Convict on 31/1/2007 at 12:18
wow they didn't teach that in high skool! :eek:
Spitter on 31/1/2007 at 12:36
Quote Posted by Briareos H
velocity = sqrt ( 2 ( pressure_std - ( 500N + mass_window * gravity_acceleration ) / area_window ) / density_air )
watch out with the pressure_std in the equation, you know you've fucked up if the result is too thigh
ignatios on 31/1/2007 at 14:10
pressure_std is calculated thusly:
46" chest + 28" waist
= pretty high
hopefully not too high but still pretty worrisome
Gingerbread Man on 31/1/2007 at 15:56
newtons to kilograms just multiply by .102 wtf
As far as the wind and magnetit forces goes, you're on your own
RocketMan on 31/1/2007 at 16:19
Quote Posted by SARGE
the magnet is holding a roof light shut in a building where the wind has broken the holding force of the magnet, normally the power to the magnet is realeased and the roof light would open on a gas spring (much like the ones on a car boot)
the holding force is acting upwards.
if thats any further help.
It should be relatively straight forward to solve but you have to provide a better description of how it all looks graphically, as well as provide us with the properties of the magnet (voltage, winding resistance, ferrite/neodymium/strontium magnet?, and any applicable masses and dimensions ie. the hinged roof)
A picture drawn in paint or something would help.
fett on 31/1/2007 at 17:07
I demand that Convict, Chimpy, and ig be banned immediately.
Also: If a train leaves Chicago going 40mph and the African cheetah runs at an average of 15 mph on Tuesdays, do you take your lunch or ride the bus to school?
CyberFish on 31/1/2007 at 17:57
Right, so you've got a roof (Is it sloping or flat?) with a window (how large a window, and does it open inwards or outwards?) set into it, with wind blowing over the building at an unknown velocity (and an unknown direction). The light is held shut by a magnet capable of exerting 500N of force to keep the window shut.
It's hard to calculate the wind speed from this, but obviously it's exerting more than 500N of force on the window. Force = pressure * area, so you can work out the air pressure by dividing 500 by the area of the window in m<sup>2</sup>. This doesn't give you the wind speed because the effect is dependant on the slope of the roof and any possible turbulence effects.
doctorfrog on 31/1/2007 at 18:02
The real question is will the train meet the cheetah first, or will the cheetah meet the train first? Either way, once we open the box, we'll find out.
