A small compass is held horizontally, the center of its needle has a distance of 0.270 m directly north of a long wire that is perpendicular to the Earth's surface. When there is no current in the wire, the
compass needle points due north, which is the direction of the horizontal component of the Earth's
magnetic field at that location. This component is parallel to the Earth's surface. When the current in
the wire is 26.3 A, the needle points 22.9∘ east of north.
(a) Does the current in the wire flow toward or away from the Earth's surface? ( 2 marks)
(b) What is the magnitude of the horizontal component of the Earth's magnetic field at the location of
the compass? (3 marks)

Explanation:

The needle is showing north south direction . when current starts flowing in the wire which is held vertical to the ground , it deflects towards east .

a )

Therefore a magnetic field towards east has been created . It is possible only if current flows towards the surface in the vertical wire .

b )

magnetic field created at the magnetic needle B = 10⁻⁷ x  2I / d where I is current and d is distance .

B = 10⁻⁷ x  2 x 26.3  / .27

= 194.81 x 10⁻⁷ T

angle of deflection of solenoid = 22.9°

Tan 22.9 = B /H

.422 = 194.81 x 10⁻⁷ / H

H = 461.63 x 10⁻⁷ T

= .46 x 10⁻⁴ T .

i need the answer to this too but idk it ; -;

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.