Answer:
Explanation:
We define the linear density of charge as:

Where L is the rod's length, in this case the semicircle's length L = πr
The potential created at the center by an differential element of charge is:

where k is the coulomb's constant
r is the distance from dq to center of the circle
Thus.

Potential at the center of the semicircle
Answer:
(2x + 4)(x - 4)=2x^2-4x-16
Answer:
Explanation:
speed is define as rate of change of distance or displacement
v=s/t
s=8 m
t=4s
v=8/4
v=2 m/s