Which rule is used to determine the direction of the magnetic field at the centre of a circular current-carrying loop?
Right-hand thumb rule
When current flows through a circular loop of wire, it produces a magnetic field whose direction at any point depends on the sense in which the current is flowing round the loop.
The right-hand thumb rule (Ampere’s rule) says that if you curl the fingers of your right hand along the direction of the current in the loop, then the extended thumb points in the direction of the magnetic field at the centre of the loop. Fleming’s left-hand rule is used for the force on a current-carrying conductor in a magnetic field, not for the field itself. Joule’s law of heating deals with the heat produced in a resistor, and Ohm’s law relates current, voltage and resistance — neither gives the direction of a magnetic field.
Hence, the answer is Right-hand thumb rule.
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The direction of the magnetic field at the centre of a current-carrying circular loop is determined by which of the following?
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Important Questions from Magnetism
What is the direction of magnetic field lines outside a magnet?
Which of the following statement is correct?
।. Magnetic field has both magnitude and direction.
II. The magnetic field inside a current-carrying straight long solenoid is the same at all points.
The magnetic effect of electric current was discovered by _____.
The important property of magnet which was exploited by navigators and travelers from the ancient times is:
The magnet used to lift and transport heavy loads like big metals, steel girders and scrap iron objects for loading and unloading purposes is known as____.
