Electric charges and fields

 

Electric Charges and Fields

  
 Problems

 

Question1.  What is the value of charge on an electron? Is a charge less than this value possible?

Solution.  e = - 1.6 x 10-19 C.

                No, charge less than this value do not exist.

 Question2. Does the motion of a body affect its charge?

 Solution. No, charge on a body does not change with the motion of the body.

Question3. Give two points of distinction between charge and mass.

Solution. The charge can be positive, negative, or zero. But mass is a positive quantity. Further, the electric charge is always conserved. But mass is not conserved as it can be changed into energy and vice-versa.

Question4. What is the basic cause of the quantization of charge?

Solution. Only integral a number of electrons can be transferred from one body to the other.

Question5. Can ever photons have a charge? If not why?

Solution. No, photons can never have a charge. This is because charge cannot exist without rest mass.

Question6. Which of the following quantities depends on the state of rest or motion of a body?

 (a) Mass (b) length (c) time (d) charge (e) charge density and (I) phase?

Solution.  Mass, length, time, and charge density depend on the state of rest or motion of a body. However, charge and phase are invariant.

Question7. Does Coulomb's law of electric force obey Newton's third law of motion?

 Solution. Yes, it obeys. Forces exerted by two charges on each other are always equal and opposite.

Question8. Is the electric force between two electrons greater than the gravitational force between them? If so, by what factor?

Solution. Yes, the electric force between two electrons is greater than the gravitational force between them by a factor of 1042.

 Question9. Electrostatic forces are much stronger than gravitational forces. Give one example.

 Solution. A charged glass rod can lift a piece of paper against the gravitational pull of the earth on this piece.

Question10. What is the dimensional formula for ?

 Solution. [M-1 L-3 T4 A2 ].

Comments

Post a Comment

please do not enter any spam link in the comment box

Popular posts from this blog

FORCE AND LAWS OF MOTION, Class IX, Part 4

Image
  If a boy wearing roller skates stands facing a wall and pushes the wall with his hands, the boy finds himself moving backward, away from the wall. It appears as if the wall also pushes the boy away. When the boy exerts a force on the wall by pushing it with his hands, then the wall exerts an equal force on the boy in the opposite direction . Since the boy is wearing roller skates, the opposite force exerted by the wall makes him backward, the boy on roller skates is exerting force on the wall towards the left side. The wall exerts an equal force on the boy towards the right side. Due to this, the boy moves in the backward direction. From this discussion, we conclude that when a boy exerts a force on the wall, the wall exerts an equal and opposite force on the boy . This is just an illustration of Newton’s third law of motion. Whenever one body exerts a force on another body, the second body exerts an equal and opposite force on the second body. The force exerted by the first bo
Read more

FORCE AND LAWS OF MOTION, Class IX, Part 3

Image
                                         In order to understand Newton’s second law of motion, we should first know the meaning of the term momentum of a moving body (or moving object). We know that a cricket ball is much heavier than a tennis ball. Suppose we throw a cricket ball and a tennis ball, both with the same speed or velocity. It will be found that more force is required to stop the cricket ball (Which has more mass) and less force is required to stop the tennis ball (which has less mass). We conclude that the force required to stop a moving body is directly proportional to its mass. If we throw two cricket balls of the same mass at different speeds or velocities, it will be found that more force is required to stop that cricket ball which is moving with higher velocity and less force is required to stop that cricket ball which is moving with higher velocity and less force is required to stop the cricket ball moving with lower velocity. So conclude that the force required to
Read more

LIGHT, Class X,, MCQ Part 1

                                                               MCQ'S MCQ Questions for Class 10 Science Light Reflection and Refraction with Answers Students can solve NCERT Class 10 Science Light Reflection and Refraction Latest Exam Pattern Multiple Choice Questions with Answers to know their preparation level. Question1. When light falls on a smooth polished surface, most of it (a) is reflected in the same direction            (b) is reflected in different directions (c) is scattered                                                                                    (d) is refracted into the second medium                                                                          Answer: a                                                                                                                      Q2. The image formed by reflection from a plane mirror is                                                            (a) real and inverted                                       
Read more