At a place, the horizontal component of earth's magnetic field is B and angle of dip is `60^@`. What is the value of horizontal component of earth's magnetic field at equator?

Explanation

To find the horizontal component of Earth's magnetic field at the equator given the horizontal component \( B \) at a certain place and the angle of dip \( \delta = 60^\circ \), we can follow these steps:

### Step 1: Understand the relationship between the components of the magnetic field
The horizontal component \( H \) of the Earth's magnetic field at any location is related to the resultant magnetic field \( R \) and the angle of dip \( \delta \) by the formula:
\[ H = R \cos(\delta) \]

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