Question

The field at a distance $r$ from a long straight wire of charge per unit length $\lambda$ is:

• A. $k\frac{\lambda }{r^2}$
• B. $k\frac{\lambda }{r}$
• C. $k\frac{\lambda }{2r}$
• D. $k\frac{2\lambda }{r}$

Answer 1

The correct option is D $k\frac{2\lambda }{r}$

The field at a distance $=r$ a long straight wire of charge per unit length $\lambda$.

then the field $V=k\frac{2\lambda }{r}$