See this suggested solution.
1. Let a force F' is the vector sum of the forces P and Q, then it is shown on the attached picture and marked with red color.
2. according to the condition the force F holds the object, then F should have the same length as the force F' and the opposite direction.
3. using the conditions described in 2. the answer is C.
Answer:
(a) The impedance in the circuit is .
(b)The resistance is .
(c) The inuctance is 0.57 H.
Explanation:
(a)
The expression for the impedance is as follows:
Here, is the rms voltage and
is the rms current.
Put and
.
Therefore, the impedance in the circuit is .
(b)
The expression for the average power is as follows;
Here, is the average power and R is the resistance.
Calculate the resistance by rearranging the above expression.
Put and
Therefore, the resistance is .
(c)
The expression for the impedance is as follows;
Here, is the inductive reactance.
Put and
.
The expression for the inductive reactance in terms of frequency is as follows;
Here, L is the inductance.
Calculate the inductance by rearranging the above expression.
Put and f=50Hz.
L=0.57 H
Therefore, the inuctance is 0.57 H.