Electronics - Parallel Circuits - Discussion

Discussion Forum : Parallel Circuits - General Questions (Q.No. 4)
4.
What is the total power loss if 2 k and 1 k parallel-connected resistors have an IT of 3 mA?
6 W
36 W
6 mW
36 mW
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
39 comments Page 2 of 4.

Azhagusurya said:   1 decade ago
Power loss p = i^2/Rt.

Rt = (r1*r2)/(r1+r2).
Rt = (2*1)M/(2+1)k.
Rt = (2/3)k.
p = (3^2)u*(2/3)k.
p = (18/3)m= 6mW.

Asha said:   1 decade ago
P = VI.....1.
V = IR......2.

Substitute above equation in 1,
we get P = I^2*R.

R = 2*1/2+1,
R = 2/3,
P = (3*10^-3)^2*(2/3)*10^3 ohm,
p = 6mW.

Irshad k a said:   1 decade ago
R = 2/2+1/2.
R = 3/2.
R = 2/3.
R = 0.6668.

P = I2R.
P = 3*3*0.6668.
P = 6(approximately).

Hims said:   1 decade ago
Rp = 2*1/2+1 = 2/3 kohm = (2/3) * 10^3 ohm.

P = i2*r.
i = 3mA = 3*10^-3A.

P = (3*10^-3)A*(3*10^-3)A* (2/3)* 10^3 ohm.
P = (3*3*2/3)W * (10^-3*10^-3*10^3).

P = (6)W*(10^-3) = 6*10^-3W.
P = 6mW.

Vinod said:   1 decade ago
parallel resistors:

1/r = 1/r1+1/r2.
1/r = 1/2+1/1.
1/r = 3/2.
r = 2/3.

p = v*i.
v = i*r.
p = i^2*r.

p = 3^2*2/3.
p = 9*2/3.
p = 6mA.

Abc said:   1 decade ago
What would be the total power loss had the circuit been connected in series?

Prasanna said:   1 decade ago
Ramprabhu is wrong,
Resistance value here given is Kohms and he consider it to be only ohms

U.suruthi said:   1 decade ago
R = (2*1)/(2+1) = 2/3.

I = 3*10^-3.

P = I^2*R.

P = (3*10^-3)^2*(2/3).

P = 6*10^-3w.

Sudhakar said:   1 decade ago
Here total current given is It=3mamp,

And R1=2kohm, R2=1kohm are in parallel,

So equivalent resistance of 2 parallel resistors is Req=R1*R2/ (R1+R2).

So Req=2kohm*1kohm/ (2kohm+1kohm).

= (2*1*kohm*kohm) / (3kohm).

=2kohm/3.

Now total power loss in a circuit is=It^2 (Req).

= (3mamp*3mamp) (2kohm/3) =6mw is the correct answer.

Anjali.r said:   1 decade ago
P=i^2*r
P=3^2*(2/3)
P=6mw


Post your comments here:

Your comments will be displayed after verification.