A becomes positive, while b is now negative. Basically, electrons are negative particles. If they go to somewhere, they make the somewhere they go to negative.
Answer:
3.6km South East
Explanation:
Displacement is the shortest distance between the starting point and the ending point and the direction it is displaced in. To calculate the displacement we can use the pythagoras theorem because the 3km East and the 2km south form the two shorter sides of a right angled triangle between the starting and ending points. So, the displacement is the length C of the triangle which we can calculate as follows:
Pythagoras Theorem:
a^2+b^2=c^2
(2)^2+(3)^2=c^(2)
4+9=c^2
Square root 13 = c
c=3.6km (1dp)
The total displacement is 3.6km and is in the approximate direction of South East (because he travelled east and south).
Hope this helped!
Answer:
Explanation:
The potential difference between one side of the wire causes the electric field inside the wire (causes the electrons to flow). However, inside the wire, it is still neutral. The electrons are just moving, the wire is not gaining or losing electrons.
The formula for work is

. Plugging in the numbers, you get:


The answer is 30 N.