A fan with copper winding in its motor consumes less power as compared to an otherwise similar fan having aluminium winding.Explain.

93. Two conductors are of same shape and size. One of copper and the other of aluminium (less conducting) are placed in an uniform electric field. The charge induced in aluminium :- (1) will be less than that in copper (2) will be more than that in copper (3) will be equal to that in copper (4) cannot be compared with that of copper ES0093

(a) An electric motor runs on a d.c. source of emf e and internal resistance r. show that the power output of the source is maximum when the current drawns by the motor is epsilon//2r . (b) Show that power output of electric motor is maximum when the back emf is one-half the source emf provided the resistance of the windings of the motor is negligible. (c) Compare and contrast carefully the situation in this excercise with that in Example 43 above.

(a) An electric motor runs on a d.c. source of emf e and internal resistance r. show that the power output of the source is maximum when the current drawns by the motor is epsilon//2r . (b) Show that power output of electric motor is maximum when the back emf is one-half the source emf provided the resistance of the windings of the motor is negligible. (c) Compare and contrast carefully the situation in this excercise with that in Example 43 above.

A fan operates at 200 volt (DC) consuming 1000W when running at full speed . It's internal wiring has resistance 1 Omega . When the fan runs at full speed , its speed becomes constant. This is because the torque due to magnetic field inside tha fan is balanced by the torque due to air resistance on the blades of the fan and torque due to friction between the fixed part and the shaft of the fan. The electrical power going into the fan is spent (i) in the internal resistance as heat, call it P_(1)(ii) in doing work against internal friction and air resistance producing heat, sound etc. call it P_(2) . When the coil of fan rotates, an emf is also induced in the coil. This opposes the external emf applied to snd the current into the fan. This emf is called back-emf,call it 'e' . Answer the following questions when the fan is running at full speed. The value of power P_(1) is

A fan operates at 200 volt (DC) consuming 1000W when running at full speed . It's internal wiring has resistance 1 Omega . When the fan runs at full speed , its speed becomes constant. This is because the torque due to magnetic field inside tha fan is balanced by the torque due to air resistance on the blades of the fan and torque due to friction between the fixed part and the shaft of the fan. The electrical power going into the fan is spent (i) in the internal resistance as heat, call it P_(1)(ii) in doing work against internal friction and air resistance producing heat, sound etc. call it P_(2) . When the coil of fan rotates, an emf is also induced in the coil. This opposes the external emf applied to snd the current into the fan. This emf is called back-emf,call it 'e' . Answer the following questions when the fan is running at full speed. The value of power P_(2) si

Explain with diagram step-by-step energy conversion in: Power plant based on wind energy :

A power transmission line feeds input power at 2300 V a step down transformer with its primary windings having 4000 turns. The output power is delivered at 230 V by the transformer. If the current in the primary of the transformer is 5A and its efficiency is 90% , the output current would be :

A power tansmission line feeds input input power at 2200 V to a step down transformer with its primary windings having 3000 turns. Find the number of turns in secondary to get the power output at 220 V.