SSC JE Electrical 2019 with solution SET-2
While estimating the overhead lines, if the number of poles required is 14, then what is the estimated number of earth sets required?
While estimating the overhead lines, the first and last pole is always earth connected and after every 3rd electrical pole, the fourth pole is earthed. Therefore, the approximate number of required ground set = 4
When the field winding is connected in series with the armature winding while supplying the load then the generator is called a series generator. Current Relations As all armature, field, and load are in series they carry the same current. IL = Ise = Ia
The combined inductance of two coils connected in series L = L1 + L2 + 2M In series adding case L1 + L2 + 2M = 0.6 H ——–(1) In series opposing case L1 + L2 − 2M = 0.1 H ——–(2) Subtracting eqn (2) from eqn (1) we get 4M = 0.5 H M = 0.125 H Let L1 = 0.2 H (since the coil when isolated, its self-inductance is 0.2 H) Putting the value of M & L1 in equation (2) 0.2 + L2 + 2 ×0.125 = 0.06 0.2 + L2 = 0.35 L2 = 0.15 H
The melting point of Eureka is 1221 to 1300 °C The melting point of Kanthal is 1,425 °C The melting point of Nichrome is 1400 °C The melting point of Graphite is 3,600°C Hence Eureka has the least range of temperature.