Physics
The GPS device in an automobile uses which communication channel?

Infrared
Satellite
Microwave
Radio frequency

ANSWER DOWNLOAD EXAMIANS APP

Physics
Railway tracks are banked on curves so that

Necessary centripetal force may be obtained from the horizontal component of the weight of the train
No frictional force may be produced between the tracks and the wheels of the train
The train may not fall down inwards
Necessary centrifugal force may be obtained from the horizontal component of the weight of the train

ANSWER DOWNLOAD EXAMIANS APP