Question { RRB, 6923 }

what happend when 230v dc motor we supplied a 23v ac supply

Answer

In an armature based dc motor, it will rotate to and fro.
After roatating 180 degree, it will rotate back again 180
degree and so on.

Question { 5715 }

what is power relation in AM system

Answer

s(t)= Ac[1+kam(t)] cos(2*pi*fct)
power of carrier component: Ac2/2
power of message component: ka*m*Ac2/2
total power: Ac^2[1+ka^2*P]/2
where P is the power of the message signal.

As there is no option of subscript and superscript, it is
very difficult to write mathematical equation.