PYQs Based test 5: Electromagnetic Fields

A parallel plate capacitor is partially filled with glass of dielectric constant 4.0 as shown below. The dielectric strengths of air and glass are 30 kV/cm and 300 kV/cm, respectively. The maximum voltage (in kilovolts), which can be applied across the capacitor without any breakdown, is ______.

The capacitance of an air-filled parallel-plate capacitor is 60 pF. When a dielectric slab whose thickness is half the distance between the plates, is placed on one of the plates covering it entirely, the capacitance becomes 86 pF. Neglecting the fringing effects, the relative permittivity of the dielectric is __________ (up to 2 decimal places).

The following four vector fields are given in Cartesian co-ordinate system. The vector field which does not satisfy the property of magnetic flux density is

A rotating conductor of 1m length is placed in a radially outward (about the z-axis) magnetic flux density (B) of 1 Tesla as shown in the figure below. The conductor is parallel to and at 1m distance from the z-axis. The speed of the conductor in r.p.m. required to induce a voltage of 1V across it, should be __________.

A transformer with toroidal core of permeability μ is shown in the figure. Assuming uniform flux density across the circular core cross-section of radius r R, and neglecting any leakage flux, the best estimate for the mean radius R is