Question

Two-point charges Q1 = 4.5 μC and Q2 = 8.5 μC are initially very far apart. They are then brought together, with a final separation of 3.5 mm. How much work does it take to bring them together?​

Answer 1

Answer:

98.4 joule

Explanation:

w = kq1q2/r

w = (9×10^9)(4.5×10^-6)(8.5×10^-6)/0.0035

w = 98.4 joule

k = 9×10^9

1mm = 1000 m

Answer 2

Given:

Value of  Charge Q1 = 4.5 μC

Value of  Charge Q2 = 8.5 μC

Final separation of the charges = 3.5 mm.

Find: Work done to bring them together

Solution:

Q1 = 4.5 * 10^ -6, Q2 = 8.5 * 10^ -6

Separation of charger be 'r' = 3.5 mm = 3.5 * 10^-3

Work done to bring them together is given by the formula :

W = K Q1 Q2 / r (Where K = 9×10^9 N ⋅ m^2 /C^2)

W = 9×10^9 * 4.5 * 10^ -6 * 8.5 * 10^ -6 / 3.5 * 10^-3

W = 98.35 Joule

The work done to bring the two charges Q1 and Q2 together is 98.35 Joule.