Answer:
4v/3
Explanation:
Assume elastic collision by the law of momentum conservation:
where v is the original speed of car 1, v1 is the final speed of car 1 and v2 is final speed of car 2. m1 and m2 are masses of car 1 and car 2, respectively
Substitute
Divide both side by , then multiply by 6 we have
So the final speed of the second car is 4/3 of the first car original speed
Answer:
On the magnitude of the charges, on their separation and on the sign of the charges
Explanation:
The magnitude of the electric force between two charges is given by
where
k is the Coulomb's constant
q1, q2 are the magnitudes of the two charges
r is the separation between the charges
From the formula, we see that the magnitude of the force depends on the following factors:
- magnitude of the two charges
- separation between the charges
Moreover, the direction of the force depends on the sign of the two charges. In fact:
- if the two charges have same sign, the force is repulsive
- if the two charges have opposite signs, the force is attractive