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I need help with this Physics Paper 2 2019 aqa Q2.1 Question

I've genuinely never in my life been more confused?? I can't link the diagram but its on PMT, "When the apparatus is assembled with the switch open, the reading on the electronic balance is set to 0.000 g. This reading changes to a positive value when the switch is closed." So apparently this means, due to Newtons 3rd Law, that the Force of the magnetic field is upwards.

The wire is not connected to the Magnet or Yolk at all, its clamped and suspended. So if the Force pushes the wire up, and then there is a resultant force downwards (Newtons 3rd Law) then how on earth does the Yolk/Magnet "know" or experience this resultant force? Especially considering we know that the upwards force, from the field, that the wire experiences has no affect on the Yolk/Magnet, but somehow the resultant force does?? It just makes no sense

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Original post
by sjalijiwcn
I've genuinely never in my life been more confused?? I can't link the diagram but its on PMT, "When the apparatus is assembled with the switch open, the reading on the electronic balance is set to 0.000 g. This reading changes to a positive value when the switch is closed." So apparently this means, due to Newtons 3rd Law, that the Force of the magnetic field is upwards.
The wire is not connected to the Magnet or Yolk at all, its clamped and suspended. So if the Force pushes the wire up, and then there is a resultant force downwards (Newtons 3rd Law) then how on earth does the Yolk/Magnet "know" or experience this resultant force? Especially considering we know that the upwards force, from the field, that the wire experiences has no affect on the Yolk/Magnet, but somehow the resultant force does?? It just makes no sense

Hi, I can't find that question. My 2019 paper 2 has Q 2.1 as internal energy of a gas. This is A level, AQA A? Friday 24th May 2019.

Reply 2

Original post
by sjalijiwcn
I've genuinely never in my life been more confused?? I can't link the diagram but its on PMT, "When the apparatus is assembled with the switch open, the reading on the electronic balance is set to 0.000 g. This reading changes to a positive value when the switch is closed." So apparently this means, due to Newtons 3rd Law, that the Force of the magnetic field is upwards.
The wire is not connected to the Magnet or Yolk at all, its clamped and suspended. So if the Force pushes the wire up, and then there is a resultant force downwards (Newtons 3rd Law) then how on earth does the Yolk/Magnet "know" or experience this resultant force? Especially considering we know that the upwards force, from the field, that the wire experiences has no affect on the Yolk/Magnet, but somehow the resultant force does?? It just makes no sense

when you let go of an apple how does the apple know that the Earth is there?
How does the Earth know that the apple is there?
We call it action at a distance
The concept of "fields" helps us to explain what's happening
Is it messenger particles?
Is it a result of curved spacetime?
Answers on a postcard

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