In transformer, bushing failure occurs due to
(i) transformer vibrations
(ii) dielectric losses
(ii) partial discharge

A circuit breaker is rated 2500 A, 2000 MVA, 33 kV, 3 sec, 3-phase oil circuit breaker. Determine the breaking current.

Breaking capacity of circuit breaker = √3*VL*Ib
VL - line voltage in volt
IL - Line current/breaking in ampere
VL = 33 kV
S = 2000 MVA

Ib = 30*1000 (in kVA)/(√3*33)
Ib = 34.99 kA

Nangal Wildlife Sanctuary is located in which state?

Consider the following statements associated with Buchholz's relays.
Statement 1: Buchholz's relay is a current operated device.
Statement 2 : Buchholz's relay is placed between the transformer tank and the conservator.

Buchholz relay is gas operated relay.
It will operate when internal fault occurs in transformer.
It is placed between tank to main conservator.
It has two contacts trip and alarm.
Use of Buchholz relay in distribution transformer is not economical.

A circular loop has its radius increasing at a rate of 2 m/s. The loop is placed perpendicular to a constant magnetic field of 0.1 Wb/m². When the radius of the loop is 2 m, the emf induced in the loop will be

emf = dΨ/dt = change of flux linkage
emf = dф/dt
emf = d(B*Area)/dt
emf = B*d(area)/dt
emf = B*d(πr²)/dt
emf = Bπ*2r*dr/dt
emf = Bπ*2r*change of radius per unit time
emf = 0.1*π*2*2
emf = 4π

Fill in the blanks with suitable Article from the given alternatives.
I heard ____interesting story yesterday