# NCERT Class 12 Physics Solutions Electric Charges And Fields

NCERT Class 12 Physics Solutions Electric Charges And Fields- NCERT Solutions prepared for CBSE students by the best teachers in Delhi.

Class XII Chapter 1 – Electric Charges And Fields Physics

Question 1.1: What is the force between two small charged spheres having charges of 2 × 10−7 C and 3 × 10−7 C placed 30 cm apart in air?

Question 1.2: The electrostatic force on a small sphere of charge 0.4 μC due to another small sphere of charge − 0.8 μC in air is 0.2 N. (a) What is the distance between the two spheres? (b) What is the force on the second sphere due to the first?

Question 1.3: Check that the ratio ke2/G memp is dimensionless. Look up a Table of Physical Constants and determine the value of this ratio. What does the ratio signify?

Question 1.4:

(a) Explain the meaning of the statement ‘electric charge of a body is quantised’.

(b) Why can one ignore quantisation of electric charge when dealing with macroscopic i.e., large scale charges?

Question 1.5: When a glass rod is rubbed with a silk cloth, charges appear on both. A similar phenomenon is observed with many other pairs of bodies. Explain how this observation is consistent with the law of conservation of charge.

Question 1.6: Four point charges qA = 2 μC, qB = −5 μC, qC = 2 μC, and qD = −5 μC are located at the corners of a square ABCD of side 10 cm. What is the force on a charge of 1 μC placed at the centre of the square?

Question 1.7:

(a) An electrostatic field line is a continuous curve. That is, a field line cannot have sudden breaks. Why not?

(b) Explain why two field lines never cross each other at any point?

Question 1.8: Two point charges qA = 3 ƒÊC and qB = .3 ƒÊC are located 20 cm apart in vacuum.

(a) What is the electric field at the midpoint O of the line AB joining the two charges?

(b) If a negative test charge of magnitude 1.5 ~ 10.9 C is placed at this point, what is the force experienced by the test charge?

Question 1.9: A system has two charges qA = 2.5 × 10−7 C and qB = −2.5 × 10−7 C located at points A: (0, 0, − 15 cm) and B: (0, 0, + 15 cm), respectively. What are the total charge and electric dipole moment of the system?

Students should free download the NCERT solutions and get better marks in exams. Studiestoday.com panel of teachers recommend students to practice questions in NCERT books and download NCERT solutions.

## Tags: Click to View or Download pdf file Click to View or Download pdf file For more study material for Physics please click here - Physics

## Latest CBSE News

• As per the latest updates, the Central Board of Secondary Education (CBSE) is thinking to stop many of its subjects. There are existing subjects in which students don’t take interest at all. In past few years there are subjects which are not entertained by the students so CBSE feels that these are better to shut these kind of subjects. The CBSE board has asked for suggestions from the schools...