Answer:

Explanation:
This problem is approached using Coulomb's law of electrostatic attraction which states that the force F of attraction or repulsion between two point charges,
and
is directly proportional to the product of the charges and inversely proportional to the square of their distance of separation R.

where k is the electrostatic constant.
We can make k the subject of formula as follows;

Since k is a constant, equation (2) implies that the ratio of the product of the of the force and the distance between two charges to the product of charges is a constant. Hence if we alter the charges or their distance of separation and take the same ratio as stated in equation(2) we will get the same result, which is k.
According to the problem, one of the two identical charges was altered from
to
and their distance of separation from
to
, this also made the force between them to change from
to
. Therefore as stated by equation (2), we can write the following;

Therefore;

From equation (4) we now make the new force
the subject of formula as follows;

then cancels out from both side of the equation, hence we obtain the following;

From equation (4) we can now write the following;

This could also be expressed as follows;

Like a seesaw, it shows that the forces aren’t equal because if it was the seesaw would stay put
Answer:
a = F-ff/m
Explanation:
According to Newton's second law of motion which states that "the rate of change in momentum of a body is directly proportional to the applied force F and acts in the direction of the force.
Mathematically;
F = ma
Since two forces acts on the cart i.e the moving force F and the frictional force Ff , we will take the sum of the forces.
∑F = ma where
m is the mass of the cart
a is its acceleration
∑F = F+(-ff )(since frictional force is an opposing force)
F - ff = ma
Dividing both sides by mass m
a = F-ff/m
Answer:
I DONT KNOW WHAT TO DO SORRY
Explanation:
EVEN ME IM NOT SURW