Question

At the magnetic north pole of the Earth, the value of the horizontal component of Earth’s magnetic field and angle of dip are respectively
A. zero, maximum
B. maximum, minimum
C. maximum, maximum
D. minimum, minimum

Answer 1

Hint: Recall the concept of the direction of the magnetic field of the Earth. Check the direction of the Earth’s magnetic field and its components. Also recall the concept of angle of dip for the Earth’s magnetic field. Determine the angle of dip of the Earth at the magnetic north pole of the Earth and check which of the options given is correct.

Complete step by step solution:
In this question, we are asked to determine the value of the horizontal component of the Earth’s magnetic field and angle of dip at the magnetic north pole of the Earth.Let us first determine the value of the horizontal component of the Earth’s magnetic field at the magnetic north pole of the Earth.We know that the magnetic lines from a magnet always start from the North Pole and end at the South Pole in order to form a loop.Hence, the same case is applied for the Earth as the Earth also has the magnetic north pole and magnetic South Pole. The Earth also behaves as a magnet.

The magnetic lines of force which determine the direction of the magnetic field originate from the magnetic north pole of the Earth and end on the magnetic south pole of the Earth and form a loop.The direction of these magnetic lines at the magnetic north pole is in the upward direction perpendicular to the surface of the Earth at the magnetic north pole and these lines then bend to form the loop.So, at the magnetic north pole of the Earth, the direction of the magnetic field is in the upward direction and the Earth has no horizontal component at the magnetic north pole.Hence, the value of the horizontal component of the Earth’s magnetic field at the magnetic north pole is zero.

Let now determine the angle of dip for the Earth’s magnetic field at the magnetic north pole of the Earth.The angle of dip for the Earth’s magnetic field is the angle between the magnetic equator of the Earth and the Earth’s magnetic field.At the magnetic north pole, the magnitude of the angle between the magnetic equator and the magnetic north pole is \[90^\circ \] which is maximum.Hence, the angle of dip is maximum at the magnetic north pole.

Hence, the correct option is A.

Note: The students should keep in mind that the angle of dip is positive for the direction of the magnetic field downward and negative for direction of magnetic field upward. Hence, the angle of dip at the magnetic north pole where the magnetic field is in the upward direction is \[ - 90^\circ \]. But we have not given the option zero and minimum hence, we have considered the magnitude of the angle of dip.