Hydrosphere - all the waters on the earth’s surface.
Answer:
Explained
Explanation:
Metals are good conductors of electricity because they contain free electrons in their atoms. The outer shell of atom's of metal have free electrons. These free electrons are responsible of electrical conductivity of metals. These electron are not bounded by the attraction forces of the nucleous. They are free to wonder in lattice of positive ion and thus allow electrical conductivity.
Periodic motion implies that the ride oscillates back and forth. The period is the time it takes to complete one cycle. Therefore it would be the swing.
The magnetic field generated by a wire carrying a current I is:

where r is the distance at which the magnetic field is measured, and

is the magnetic permeability in vacuum.
The problem says that the magnetic field at a distance r=12 cm=0.12 m from the wire must be no larger than

. Substituting these values, we can find the maximum value of the current I that the wire can carry: