Two point charges are separated by 6 cm. The attractive force between them is 20 N. Find the force between them when they are separated by 12 cm. (Why can you solve this problem without knowing the magnitudes of the charges?)
Step 1 of 3
Solution 1P The attractive force between two point is separated by 6 cm is 20 N. Find the electrical force between the charges when they are separated by 12 cm. q q By coulomb’s law F = 12 2 r The ratio of the forces at the two distance F q122 6 = 6 F 12 q 122 12 2 = 122 6 144 = 36 = 4 The force at 6 cm is 4 times a large as at 12 cm. Thus the force at 12 cm is 20 N/4 = 5N. The charge attracting have equal magnitude, what is the magnitude of each charge From the coulomb’s law q q F = k 12 2 r q 2 = k 2 r 2 q = F× r k 20×3.6×10 3 = 9 9×10 2 -12 q = 8×10 12 q = 8 × 10 q = 2.83 ×10 C -6
Textbook: Conceptual Physics
Author: Paul G. Hewitt
Since the solution to 1P from 22 chapter was answered, more than 389 students have viewed the full step-by-step answer. The answer to “Two point charges are separated by 6 cm. The attractive force between them is 20 N. Find the force between them when they are separated by 12 cm. (Why can you solve this problem without knowing the magnitudes of the charges?)” is broken down into a number of easy to follow steps, and 41 words. This textbook survival guide was created for the textbook: Conceptual Physics, edition: 12. Conceptual Physics was written by and is associated to the ISBN: 9780321909107. This full solution covers the following key subjects: separated, Charges, Force, knowing, Find. This expansive textbook survival guide covers 45 chapters, and 4650 solutions. The full step-by-step solution to problem: 1P from chapter: 22 was answered by , our top Physics solution expert on 04/03/17, 08:01AM.