New answers tagged electrical
4
Note the problem specifies the load is "delta connected". There is no neutral connection to measure phase voltage ($V_{LN}$) against.
Also note the supply frequency is 60 Hz. 208 V is a common line voltage ($V_{LL}$) in the US (which uses a 60 Hz supply), with corresponding phase voltage of 120 V. You are using a US text (Sarma et al, from another ...
1
A thorny problem indeed. Try having a grounded terminal or surface available nearby, and touch it after each petting stroke so the charge cannot accumulate. Also try touching the kitty in a relatively insensitive zone (hard with kitties!) before beginning each petting stroke. Let us know here the results of your experiments!
0
I've tried to put them all in similar units (I opted for mW, however there are a few problems
i.e.:
the reported power density is at different units which are not directly comparable. For example
Voltage/surface area
Voltage/volume
Voltage
electric current/surface area
the Cordyline Fruticosa has a very high value which is probably due to some mistyping ...
2
Some ways to remove static electricity are:
Use a humidifier to humidify the air in the room where George
Valentine gets petted.
If you have carpets or you sit in a fabric covered chair while
petting George Valentine treat the carpets and the chair with anti
static chemicals - usually via a spray.
Rub the upholstery of the chair with a dryer sheet
...
1
One moderately practical method to reduce or remove static shocks while petting a feline would be to have a petting mat. It should be a fabric panel or similar substance with metallic threads.
The above image from the linked Amazon page is a 20 cm square of fabric, 30% silver threads. Somewhat impractical to this concept is that at least one set of toe-...
1
Make a crank axle to lift and lower the coop door without having to reverse the motor. A full cycle would entail: start, stop, start, stop. Motor on-time for each start run is all that is needed.
0
Your idea is remotely possible but not practical. "Possible" because, surprisingly, I once saw an iron rod several feet long get magnetized by getting struck on an end while it was held in an NS direction. It was able to pick up iron filings. I can't imagine how you'd find a capacitor, or a length of suitable wire to do what you suggested.
An ...
1
I believe the method mentioned involves rolling said needle on a charged cloth.
Even if both the needle and the cloth become charged, the key is to not discharge them. As you roll the needle, the charge flows around it, causing the same effect as flowing electricity through coils around a stationary needle.
The key is not in if but in how. Depends is an ...
-1
The method sounds questionable. A compass needle needs to have a defined North and South magnetization. Does the method define exactly how to assure this? Bear in mind that the north geographic pole of the earth has a south magnetic pole (albeit offset by a few degrees); the north pointing end of the needle needs to be magnetized as a north pole. If these ...
0
Torque is equal to angular acceleration times moment of inertia of your board, idealized to$ \ 1/12mL^2$.
There are interesting points to check for though.
Whit a small defect in symmetry your board can turn into a propeller and create a lift.
If the face thickness is not insignificant the whirling of the air current can become very complex.
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