The main sources of Errors in Permanent Magnet moving Coil (PMMC) are due to : -

 The main sources of Errors in Permanent Magnet moving Coil (PMMC) are due to : - a) weaking of the permanent magnet due to aging at temperature effects b) weaking of spring due to aging and temperature effects c) change of resistance of the moving coil with temperature d) all the above
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 The main sources of Errors in Permanent Magnet moving Coil (PMMC) are due to : - a) weaking of the permanent magnet due to aging at temperature effects b) weaking of spring due to aging and temperature effects c) change of resistance of the moving coil with temperature d) all the above

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