The field coil of a two-pole $$d.c.$$ series motor is made up of two identical sections In one case
$$(i)$$ of two sections of the field coil are connected in series, and in another case
$$(ii)$$ the two sections are connected in parallel. If the motor takes the rated current in both the cases, then ratio of torque $$(1):$$ torque $$(2)$$ and speed $$(1):$$ speed $$(2)$$ respectively are

A $$5$$ $$kW,$$ $$200V$$ $$d.c.$$ shunt motor has an armature resistance of $$1$$ $$ohm$$ and shunt field resistance of $$100$$ $$ohms.$$ At no-load, the motor draws $$6A$$ from a $$200$$ $$V$$ supply and runs at $$1000$$ $$rpm.$$ The rotational loss of the machine is ______________ $$W$$ and the no load torque is ____________ $$N$$-$$m$$

A separately excited $$d.c.$$ motor has an armature resistance of $$0.5$$ $$ohm.$$ It runs off a $$250$$ $$V$$ $$d.c.$$ supply drawing an armature current of $$20$$ $$A$$ at $$1,500$$ $$rpm.$$ The torque developed for an armature current of $$10$$ $$A$$ will be __________ for the same field current.