Compound machines have two or more simple machines
We are asked to know the reason why magnetic dipole can be written as U = -m *B. The reason for this was that the negative sign is just showing or indicating the direction of the force. If it if negative, it means that the work done is opposite to the force field.
Answer:
The resonant frequency of this circuit is 14.5 kHz.
Explanation:
Given that,
Inductance of a parallel LCR circuit, 
Capacitance of parallel LCR circuit, 
At resonance the inductive reactance becomes equal to the capacitive reactance. The resonant frequency is given by :



or
f = 14.5 kHz
So, the resonant frequency of this circuit is 14.5 kHz. Hence, this is the required solution.
Answer:
1.56 J
Explanation:
The potential energy only depends on the vertical height from the ground level.
We consider the ground level to have zero P.E.
So when it is 2 m above the ground level,
P.E. = mgh
= 0.078×10×2
= 1.56 J