Answer:

Explanation:
we know angular velocity in terms of moment of inertia and angular speed
ω .... (1)
moment of inertia of rod rotating about its center of length b
........ .(2)
using v = ωr
where w is angular velocity
and r is radius of rod which is equal to b
so we get 2v = ωb
ω = 2v/b ................. (3)
here velocity is two time because two opposite ends are moving opposite with a velocity v so net velocity will be 2v
put second and third equation in ist equation
×
so final answer will be 
the electric force decreases because the distance has an indirect relationship to the force
Explanation:
The electric force between two objects is given by

where
k is the Coulomb's constant
q1 and q2 are the charges of the two objects
r is the distance between the two objects
As we can see from the formula, the magnitude of the force is inversely proportional to the square of the distance: so, when the distance between the object increases, the magnitude of the force decreases.
To solve this problem we will apply the concepts related to the Impulse which can be defined as the product between mass and the total change in velocity. That is to say

Here,
m = mass
Change in velocity
As we can see there are two types of velocity at the moment the object makes the impact,
the first would be the initial velocity perpendicular to the wall and the final velocity perpendicular to the wall.
That is to say,


El angulo dado es de 45° y la velocidad de 25, por tanto


The change of sign indicates a change in the direction of the object.
Therefore the impulse would be as


The negative sign indicates that the pulse is in the opposite direction of the initial velocity.