Compared to permanent magnets, why are electromagnets more useful in many modern technologies?
O A. In permanent magnets, the strength of the magnetic field is more
consistent.
O B. To use an electromagnet, a power supply is not necessary.
O C. Strong permanent magnets are too large to use.
O D. By controlling the current, electromagnets can be turned on and
off.

v=ir = 3x15 =45 v

if they have a finite resultant

talk back to him about the sport and show him your expertise or leave the room

the order for strong to weak forces such as

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force

the fundamental forces are those forces that act between to objects or element to make interactions. there are four types of fundamental forces such as strong and weak nuclear forces (due to protons and electrons), electromagnetic force (due to the motion of electrons) and gravitational force (due to orbital movement of the planet). if these forces are arranged on the basis of their maximum strength then the order is

strong nuclear force → electromegnetic force → weak nuclear force → gravitational force