Which factors affect the strength of an electromagnet? check all that apply. the direction of the current flowing through the wire the amount of current flowing through the wire the number of coils in the wire the material of the wire the material of the core

the amount of current flowing through the wire

the number of coils in the wire

the material of the core

Explanation:

When current is passes through a coil, it generates magnetic field. This forms an electromagnet. The strength of the magnetic field generated by an electromagnet can be controlled. It depends on the following factors:

B = μ n I

where μ is the permeability, n is the number of turns in the wire and I is the current.

The strength increases with in number of coils and amount of current.

Other than this, the magnetic field strength increases if the core is made of magnetic material such as Iron.

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.