Multiple Choice Motor Question (2 Viewers)

[Ambility]

http://i.imgur.com/LUm5sLU.png

I answered A but the answers say D.

The motor will rotate continuously with an AC source, that I know. In the picture though, the motor is in a position which I believe won't experience any rotation if connected to a DC source, which is why I chose A.

Am I wrong or is it just a bad question?

 

[Paradoxica]

Doesn't the motor oscillate under direct current?

 

[Ambility]

Doesn't the motor oscillate under direct current?

I believe it oscillates around the point it is pictured at in the diagram. But I also believe if it were to be in that point initially, it wont oscillate.

 

[leehuan]

Regardless of the minuscule oscillation the DC current is going to try to pull the motor apart (force still acts up/down). The question is dodgy and I reckon the HSC wants to see A but because the motor is being pulled apart, that's going to cause a tiny bit of motion.