The angle which the direction of the earth magnetic field makes with the horizontal at a palace is know as.

Analyze the question: We need the name for the angle between the Earth's magnetic field direction at a place and the horizontal.

Concept: At any point on Earth, the magnetic field has two components:

• A horizontal component (H)
• A vertical component (V)

The resultant field points at some angle to the horizontal. This angle is the angle of dip (also called the angle of inclination). It is measured with a dip circle.

• At the magnetic equator, the dip is 0° (the field is horizontal).
• At the magnetic poles, the dip is 90° (the field is vertical).

The relationship is: tan θ = V/H, where θ is the angle of dip.

Checking each option:

• A. Angle of contact: This is the angle between a liquid surface and a solid wall, and it belongs to surface tension. It is not magnetism.
• B. Angle of dip: This is the angle between the Earth's total magnetic field and the horizontal. It matches the question.
• C. Angle of declination: This is the angle between magnetic north (the magnetic meridian) and geographic north (the geographic meridian). It is measured in the horizontal plane, not from the horizontal.
• D. Magnetic meridian: This is a vertical plane containing the Earth's magnetic field at a place. It is not an angle.

Answer: B, angle of dip.

Exam tip: Remember the difference this way:

• Dip means the field tilts down (vertical angle).
• Declination means the compass deviates from true north (horizontal angle).