In electrostatic field $$\nabla\times\overrightarrow E\equiv0$$

Static magnetic fields induce currents in closed conducting loops.

$$A$$ $$\,\,5 \times 7$$ matrix has all its entries equal to $$1.$$ Then the rank of a matrix is

The eigen values of the matrix $$\left[ {\matrix{ a & 1 \cr a & 1 \cr } } \right]$$ are