In a wire AB, 25*10^21 electrons move from point A and B in 100 seconds. What is the current between A and B? What is the direction of this current?

40 A, current is from B to A

Explanation:

The current in a wire is defined as:

where

q is the amount of charge passing a given point of the wire in a time interval t

The charge passing through a given point can be written as

where

N is the number of electrons

is the charge of one electron

So we can rewrite the equation as

In this problem:

is the number of electrons

t = 100 s is the time interval

Substituting, we find the current:

Moreover, the direction of a current is defined as the direction of positive charges moving. Here, the charge carriers are electrons (which are negatively charged), so the direction of the current is opposite to the direction of motion of the electrons: therefore, since the electrons move from A to B, the direction of the current is from B to A.

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