Coulomb's Laws

Two protons move parallel to each other, keeping distance r between them, both moving with same velocity $\overrightarrow{\text{V}}$. Then the ratio of the electric and magnetic force of interaction between them is

A charge $q$ is placed at the centre of the line joining two equal charges $Q$. If the system of charges be in equilibrium, then find minimum value of charge $Q$ from the given options. ($e\to$charge of an electron)

The centres of two identical small conducting spheres are $1 \mathrm{m}$ apart. They carry charges of opposite kind and attract each other with a force $F$. When they are connected by a conducting thin wire they repel each other with a force $\frac{F}{3}.$ What is the ratio of the magnitude of charges carried by the spheres initially?

A charge $Q$ is placed at each of the two opposite corners of a square. A charge $q$ is placed at each of the other two corners. If the resultant force on $Q$ is zero, then

Electric charges of $1 \mathrm{\mu C},-1 \mathrm{\mu C}$ and $2 \mathrm{\mu C}$ are placed in air at the corners $A,B$ and $C$ respectively of an equilateral triangle $ABC$ having length of each side $10 \mathrm{cm}.$ The resultant force on the charge at $C$ is

Why visualization is important in learning?

How do you visualize positive thinking?

Why can't I visualize anything?

What is the process of visualization?

How do you find the point charge?

WHAT IS A in dimensional formula?

A quantity X is given by ε₀L . where ε₀ is the permittivity of free space, L is length, ΔV is potential difference and Δt is time interval. The dimensional formula for X is the same as that of

The dimensions of permittivity ε0 are 

What is the Formula for Relative Permittivity?

What are the dimensions of electrical permittivity?

Two identical conducting spheres with negligible volume have $2.1 \mathrm{nC}$ and $-0.1 \mathrm{nC}$ charges, respectively. They are brought into contact and then separated by a distance of $0.5 \mathrm{m}.$ The electrostatic force acting between the spheres is $\times {10}^{-9} \mathrm{N}.$ $[$Given : $4{\mathrm{\pi \epsilon }}_0=\frac{1}{9\times {10}^9}$ SI unit $]$

Two small spheres each of mass $10 \mathrm{mg}$ are suspended from a point by threads $0.5 \mathrm{m}$ long. They are equally charged and repel each other to a distance of $0.20 \mathrm{m}.$ Then charge on each of the sphere is $\frac{\mathrm{a}}{21}\times {10}^{-8} \mathrm{C}.$ The value of $\text{'}\mathrm{a}\text{'}$ will be __________ .

A charge $+q$ is situated at a distance '$d$' away from both the sides of a grounded conducting '$L$' shaped sheet as shown in the figure.

The force acting on the charge $+q$ is