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The only 2 Ways I can think about at the moment is either using the bars as compasses on a piece of string. Or, usually magnets are stronger at the poles so you may be able to feel this difference when comparing the two bars against each other.
 
Question 3 - Answer.

It looks like we have a winner (post 50 ElectroChem).

All you need to do is create a T with the 2 pieces of metal, if the vertical piece is the magnet it will stick to the middle of the horizontal steel and vice versa if the vertical is the steel it won't stick to the horizontal piece because it is at the centre of the bar magnet where there is no real magnetic effect, the ends of the magnet contain the strong fields N and S.
 
Question 4 - Heating things up.

I decided to go to bed and set the heating to stay on for 1hr before it clicks off, assuming the heating stays on constantly and warms the room then can I take it that the air within the room now has more energy in it when the hour is up and the room is warmer?... No simple yes/no answers, please explain your answer.
 
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Energy can be stored or transferred in different ways from place to place and this includes gasses. Hot gasses contain more energy than cold gasses. At an atomic level, the kinetic energy of the atoms increase with temperature which means more electrons have the energy needed to move a current. Although the increased temperature will also have increased the resistance of the gasses. Which now makes me think that the increased stored energy in the air can not be used unless it is changed back into something else. I feel I’ve forgotten something important but I cant remember what it is?
 
Energy is put into the room by the heater and this is seen by the temp rising, somewhere. The air in the room is warmed by the heater and by contact with the walls of the room which are heated by radiation, and in fact by DW himself if he stays in room. But the air may be "changed out" by ventilation and so if there is sufficient draught (and the outside air temp is low etc) then room air temp may be lower.
Assuming powerful radiator and correct insulation and ventilation, then air temp rises and hotter air has more energy. Where's my brandy?
 
Not seeing anyone near yet, the actual answer is one of three:-

The air within the room contains -

-MORE
-LESS
-THE SAME AMOUNT OF

energy after the heating has warmed the room up.

Note the room temperature has risen over this hour period, this is not a trick question either, all answers must have an explanation.
 
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Ok - more - heat input makes the air molecules move faster which is seen as temp increase. Just like my hot cup o tea :)
 
Energy is put into the room by the heater and this is seen by the temp rising, somewhere. The air in the room is warmed by the heater and by contact with the walls of the room which are heated by radiation, and in fact by DW himself if he stays in room. But the air may be "changed out" by ventilation and so if there is sufficient draught (and the outside air temp is low etc) then room air temp may be lower.
Assuming powerful radiator and correct insulation and ventilation, then air temp rises and hotter air has more energy. Where's my brandy?

That’s it! You’ve hit the nail on the head there. The heat losses in the room through conduction needs to heat the outside world to at least the same temperature before the temperature can begin to rise inside the room. The very reason heaven is hotter than hell. The good thing is, we can now blame global warning on DW for leaving the heating on and going to bed. Give it another 50 years and we will be able to go swimming in the see without a hat and scarf on.:)
 
You lads are not getting the jist of this thread, I post brainteasers that you may think you know the answer to but when you think about it, it more complex, no one has touched on the correct answer or the reason.
I can say that the air temp does in deed rise but losses to walls furniture etc are not a concern and from this post you should work out the the total energy level of the air must now either remain the same or be less considering I just said no one has given the correct answer yet.

Back over to you :)
 

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