Define reference point

plz help me

a basis or standard for evaluation, assessment, or comparison; a criterion.

Explanation:

Definition of reference point. : something that is used to judge or understand something else The professor used the study as a reference point for evaluating and discussing other theories.

something that is used to judge or understand something else

Explanation:

The professor used the study as a reference point for evaluating and discussing other theories.

need to see circuit to get time constant

a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.