The accuracy of D’ Arsonval movements used in common laboratory meters is about ________ of the full-scale reading.

D’ Arsonval movement or PMMC:

• The Deflection of the pointer is directly proportional to the current flowing in the coil.
• The accuracy of D’ Arsonval movements used in common laboratory meters is about 1% of the full-scale reading.
• Note that D' Arsonval moment responds for the average value of measured quantity.

Additional Information

D’ Arsonval movement Application:

Moving coil Galvanometer: 

It is a device that is used to measure and detect a small amount of electric charge i.e. electric current.

It is the most sensitive device and used in many electrical instruments. It is the major basic component of Ammeter and Voltmeter.

Principle:

Moving coil galvanometer is based on the fact that when a current-carrying rectangular coil is placed in a magnetic field it experiences a torque.

Disadvantages:

• Some errors may set in due to ageing of control springs and the permanent magnet.
• Friction due to jewel-pivot suspension.