Three objects are brought close to one another, two at a time. When objects A and B are brought together, they attract. When objects B and C are brought together, they repel. Which of the following are necessarily true?
Correct answer: B. Objects A and C possess charges of opposite sign
- A. Objects A and C possess charges of the same sign
- B. Objects A and C possess charges of opposite sign
- C. All three objects possess charges of the same sign
- D. Additional experiments must be performed to determine information about the charges on the objects
Explanation
The key to solving this problem lies in understanding the fundamental electrostatic principle that like charges repel and opposite charges attract. Objects A and B attract, indicating they have opposite charges. Objects B and C repel, indicating they have the same charge. Therefore, Objects A and C must have opposite charges. Option A is incorrect because if A and C had the same sign, they would repel each other. Option C is incorrect because if all three had the same sign, they would all repel each other, which contradicts the given interactions. Option D is unnecessary because the provided interactions already offer enough information to determine the charge relationships.
Last updated
About Electrostatics
Electrostatics describes forces between charges through Coulomb's law, electric fields and field intensity, then uses electric potential to measure energy per unit charge. Capacitors store charge and electrical energy, with capacitance depending on geometry and dielectric material, not simply on the amount of charge present.
Practise Electrostatics
831 free Electrostatics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
1/C_eq = 1/C_1 + 1/C_2 + 1/C_3 + ... + 1/C_n
1 N/C equals to:
1 volt x 1 ampere is equal to:
10 V potential difference is applied across the plate of the 1 µF capacitor. What is the energy stored in the capacitor?
12 J work is to be done against an existing electric field to take a charge of 0.01C from A to B. Find the potential difference between B and A: