The equivalent capacitance of the given circuit will be A 3h

The equivalent capacitance of the given circuit will be: A 3hp induction motor is drawing 2400W power at 0.88 pf. The efficiency of the motor will be: The armature voltage of DC motor is always_____the terminal voltage.

Solution

4)(a) Two capacitances in series C1 and C2 Equivalent capacitance Ceq=C1*C2/(C1+C2)

Two capacitances in parallel C1 and C2 Equivalent capacitance Ceq=C1+C2

In this circuit two 2uF capacitors in parallel Ceq=2*2/(2+2)=1uF

which is in parallel with 1uF So total capacitance CT=1+1=2uF

Equivalent capacitance of the circuit is 2 uF

5) (a) Input Power =2400 W

Output Power =3 hp=3*745.7=2237.1 W

%Efficiency=Output/Input=(2237.1/2400)*100=93.21 %

6) (b) Relation between armature voltage E and terminal voltage V of DC motor is E=V-I*Ra

Ra= armature resistance

So there will be armature drop always

the armature volatge is always less than terminal voltage