The efficiency is 100%, which is considered a poor heating efficiency. It is 100% because all light, motion, etc produced by the heater at some point becomes dissipated to heat.
Same heating efficiency have all other completely-in-door devices: heating with a TV set is as efficient as an electr...
@waxeagle An electric heat pump can have >100% efficiency if you define efficiency as Heat output (in joules) over Electrical input in joules. This only seems to violate the laws of thermodynamics. What's really happening is electricity is being used to MOVE heat. That is, the point of a heat pump isn't to convert electrical energy to heat energy. We're taking heat energy that already exists, and are delivering it to where we want it.
But, if you're talking about a conversion source of heat, then no. You can't get more joules out than you put in.
@BMitch What are you going to do when the magnetic field from your "collection" starts wiping your credit cards, causing homing pigeons to crash into your house, etc.
Joule heating, also known as ohmic heating and resistive heating, is the process by which the passage of an electric current through a conductor releases heat. It was first studied by James Prescott Joule in 1841. Joule immersed a length of wire in a fixed mass of water and measured the temperature rise due to a known current flowing through the wire for a 30 minute period. By varying the current and the length of the wire he deduced that the heat produced was proportional to the square of the current multiplied by the electrical resistance of the wire.
:Q \propto I^2 \cdot R
This relat...
@TheEvilGreebo Does that mean you can't burn your retinas out with a laser pointer (as long as you're wearing your glasses)?
I am converting hallway storage into a wardrobe. The dimensions are
h 234cm
W 132cm
D 45cm
I would like to put up two rails for clothing and some shelving for lose items
My question is how would I fit the rails into plasterboard style walls so they can support the weight of potentially many ...
I've got some in an old closet like that. One side is drilled, and the other is notched to drop the other end in. The notch is at a 45 degree angle, sloping down from the back of the closet so that when you tug on the hangers it won't pop out.
@Aaron The problem is, when you go to grab a shirt and it gets hung up on the hanger. You could yank the rail right out of the wall.
Anchors may be rated at 50-75 lbs. But that's probably 50-75 lbs. when the anchors completely ripped out of the wall. Not to mention it was in brand new drywall, which was installed correctly.
If you have toggle bolts in drywall behind a hanging rail support like that, and you pull hard enough to yank the rail out of the wall, I must not be using hangars correctly
Sometimes you can make an educated guess. Studs would be next to any light switches or outlets on the wall, and hopefully 16" OC from that point. You may find nail holes in trim which should be on the studs. And one side of each wall should be on a stud. That said, much of that is the case with drywall so you may have less luck with older homes and plaster walls.