Question 454: AC fundamentals

Question

Which of the following combinations should be selected for better tuning of an L-C-R circuit used for combination ?

Accepted Answer

Quality factor of an L-C-R circuit is given by,
Q = $${1 \over R}\sqrt {{L \over C}} $$
So, Q
1
= $${1 \over {20}}\sqrt {{{1.5} \over {35 	imes {{10}^{ - 6}}}}} $$ = 10.35
Q
2
= $${1 \over {25}}\sqrt {{{2.5} \over {45 	imes {{10}^{ - 6}}}}} $$ = 9.43
Q
3
= $${1 \over {15}}\sqrt {{{3.5} \over {30 	imes {{10}^{ - 6}}}}} $$ = 22.77
Q
4
= $${1 \over {25}}\sqrt {{{1.5} \over {45 	imes {{10}^{ - 6}}}}} $$ = 7.30
As Q
3
is maximum of Q
1
, Q
2
, Q
3
, and Q
4
. Hence, option (c) should be selected for better tuning of an L-C-R circuit.

Answer

R = 20 $$\Omega $$, L = 1.5 H, C = 35 $$\mu $$F

Answer

R = 25 $$\Omega $$, L = 2.5 H, C = 45 $$\mu $$F

Answer

R = 15 $$\Omega $$, L = 3.5 H, C = 30 $$\mu $$F

Answer

R = 25 $$\Omega $$, L = 1.5 H, C = 45 $$\mu $$F

AC fundamentals

Which of the following combinations should be selected for better tuning of an L-C-R circuit used for combination ?

Choose the correct answer: