GATE EE 2020 Question Paper (08-Feb-2020) (Shift 1)

A non-ideal diode is biased with a voltage of -0.03 V, and a diode current of I₁ is measured. The thermal voltage is 26 mV and the ideality factor for the diode is 15/13. The voltage, in V, at which the measured current increases to 1.5 I₁ is closest to:

A benchtop dc power supply acts as an ideal 4 A current source as long as its terminal voltage is below 10 V. Beyond this point, it begins to behave as an ideal 10 V voltage source for all load currents going down to 0 A. When connected to an ideal rheostat, find the load resistance value at which maximum power is transferred, and the corresponding load voltage and current.

The static electric field inside a dielectric medium with relative permittivity εᵣ = 2.25, expressed in cylindrical coordinate system is given by the following expression

$E=a_{r}2r+a_{\varphi }\left(\frac{3}{r}\right)+a_{z}6$

Where aᵣ, a${}_{\text{ϕ}}$, a${}_z$ are unit vectors along r, ϕ and z directions, respectively. If the above expression represents a valid electrostatic field inside the medium, then the volume charge density associated with this field in terms of free space permittvity, ε₀, in SI units is given by

Consider a permanent magnet dc (PMDC) motor which is initially at rest. At t = 0, a dc voltage of 5 V is applied to the motor. Its speed monotonically increases from 0 rad/s to 6.32 rad/s in 0.5 s and finally settles to 10 rad/s. Assuming that the armature inductance of the motor is negligible, the transfer function for the motor is

Which of the following options is correct for the system shown below?