Physics
Superconductors are substances which

offer high resistance to the flow of current
conduct electricity at low temperature
offer no resistance to the flow of electricity
conduct electricity at high temperatures

ANSWER DOWNLOAD EXAMIANS APP

Physics
Railway tracks are banked on curves

the train may not fly off in the opposite direction
necessary centripetal force may be obtained from the horizontal component of the weight of the train
necessary centrifugal force may be obtained from the horizontal component weight of the train
to avoid frictional force between the tracks and wheels

ANSWER DOWNLOAD EXAMIANS APP