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If the net outward flux through the surface of the box were zero, could you conclude that there were no charges inside the box? Why or why not?
Ans: No. The net flux entering out through a body depends on the net charge contained in the body. If the net flux is given to be zero, then it can be inferred that the net charge inside the body is...
Careful measurement of the electric field at the surface of a black box indicate that the net outward flux through the surface of the box is 
a) What is the net charge inside the box?
Ans: It is given that: Net outward flux through surface of the box, $\phi=8.0 \times 10^{3} \mathrm{Nr}^{2} / \mathrm{C}$. For a body containing net charge a, flux is given by...
What is the net flux of the uniform electric field of exercise 
through a cube of side 
oriented so that its faces are parallel to the coordinate planes?
Ans: It is given that all the faces of the cube are parallel to the coordinate planes. Clearly, the number of field lines entering the cube is equal to the number of field lines entering out of the...
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. Ans: Rubbing is a phenomenon in which there is production of charges equal in
Ans: Since unlike charges attract and like charges repel each other, the particles 1 and 2 moving towards the positively charged plate are negatively charged whereas the particle 3 that moves...
Why can one ignore the quantization of electric charge when dealing with macroscopic i.e., large scale charge?
Ans: When dealing with macroscopic or large-scale charges, the charges used are huge in number as compared to the magnitude of electric charge. Hence, the quantization of electric charge is of no...
Explain the meaning of the statement ‘electric charge of a body is quantized”.
Ans: The statement 'electric charge of a body is quantized' suggests that only integral $(1,2,3,4, \ldots, \mathrm{n})$ number of electrons can be transferred from one body to another. This further...
An electric dipole when held at 
with respect to a uniform electric field of 
experiences a torque of 
. Calculate dipole moment of the dipole?
Ans: It is given that $$ \begin{array}{l} \theta=30^{\circ} \\ \tau=9 \times 10^{-26} \mathrm{Nm} \\ E=10^{4} \mathrm{~N} / \mathrm{C} \end{array} $$ Dipole moment P needs to be calculated. It is...
The graph shows the variation of voltage 
across the plates of two capacitors 
and 
versus increase of charge 
stored on them. Which of the two capacitors have higher capacitance? Give reason for your answer.
Ans: It is known that $c=\frac{Q}{V}$ Clearly, for a given charge $\mathrm{Q}$. $c \propto \frac{1}{V}$ Now, from the given graph, it is seen that $\mathrm{V}_{\mathrm{A}}
No two electric lines of force can intersect each other. Why?
Ans: Two electric lines of force can never intersect each other. Suppose if they intersect, then at the point of intersection, there can be two tangents drawn. These two tangents are supposed to...
A free proton and a free electron are placed in a uniform field. Which of the two experiences greater force and greater acceleration?
Ans: Force on both the electron as well as the proton in the uniform field would be equal because $\mathrm{F}=\mathrm{kq}$ and it is known that charge on both electron and proton are the same. On...
Define one coulomb.
Ans: Charge on a body is said to be 1 coulomb if it experiences a force of repulsion or attraction of $9 \times 10^{9} \mathrm{~N}$ from another equal charge when they are separated by a distance of...
Which physical quantity has its S.I. unit
1. 
?
2. 
?
Ans: 1.The S.I. unit of electric dipole moment is $\mathrm{Cm}$. 2. The S.I. unit of electric field intensity is N/C.