Question

1)An RLC circuit is connected to 240V A.C supply.At resonance what are the values of VR,VL,VC ?
2)Point charges q1 and q2 are placed in air at distance r.What isThe ratio of the force on charge q1 by charge q2 and force on charge q2 by charge q1?

Answer 1

    In  a series RLC circuit, at resonance, the reactance and the voltage across the inductor cancel those of the capacitor. They are both imaginary and of opposite signs.

   Resonance frequency = ω₀ = 1/√(LC)

  Voltage across R = V_in = 240 V = input voltage.
  So current = i(t) = V_in / R  
  
  Voltage across Inductor L =  j ω₀ L * i(t) = j √(L/C) * V_in / R
  Voltage across Capacitor = - j √(L/C) * V_in / R
                                           = -1 * Voltage across L.

The potentials across L & C, depend on the values of C, L and R.

If the circuit is RLC connected in PARALLEL, then the voltage across all components is the same = 240V.

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2)  Magnitude of Force on charge q1 by charge q2
        = Magnitude of force on charge q2 by charge q1
            = Coulomb's force = 1/(4π ε₀) * q1 q2 / d²

      Same force, but in opposite directions on different charges.

Answer 2

Explanation:

The gravitational force is a force that attracts any two objects with mass. We call the gravitational force attractive because it always tries to pull masses together, it never pushes them apart.