When charged particles are separated by an infinite dis- tance, the electric potential energy of the pair is zero. When 19. 7. the particles are brought close, the electric potential energy of a pair with the same sign is positive, whereas the electric potential energy of a pair with opposite signs is negative. Give a physical explanation of this statement.

Explanation:

Potential energy Is given as.

U=kq1q2/r

Where k is a constant

q1 is charge

And q2 is also a charge

r is the distant between the two charges

When distance between the two charges is infinity then, the potential energy will b zero

U=kq1q2/∞

Therefore

U=0

Thus, the potential energy is zero when charged particles are separated by an infinite distance.

Let considered that both charges are positive.

Then U becomes

U=k(+q1)(+q2)/r

This shows that the energy is positive when the charges are positively charge. Also if the charges are also both negative charged the total energy will also be positive

U=k(-q1)(-q2)/r.

Both when their are opposite charges, the energy will be negative

U=k(-q1)(+q2)/r

U will be negative

b) 10 minutes

girls stopped for 10 minutes.