Question

A voltage of peak value 283 V and varying frequency is applied to series LCR combination in which R =3$\Omega$ L = 25 mH and C = 400 $\mu F$.Then the frequency (in Hz) of the source at which maximum power is dissipated in the above is

• A. 51.5
• B. 50.7
• C. 51.1
• D. 50.3

Answer 1

Answer: (D)

50.3

Answer 2

: Here, , $V_{0} = 283V,R = 3\Omega,L = 25 \times 10^{- 3}H$

$C = 400\mu F = 4 \times 10^{- 4}F$

Maximum power is dissipated at resonance, for which

$\upsilon = \frac{1}{2\pi\sqrt{LC}} = \frac{1 \times 7}{2 \times 22\sqrt{25 \times 10^{- 3} \times 4 \times 10^{- 4}}}$

$= \frac{7 \times 10^{3}}{44\sqrt{10}} = 50.3Hz$