How Much Charge Passes Through the Lamp in 1 Minute?

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The discussion centers on calculating the charge passing through a lamp given two different ammeter readings of 1.2 A and 1.0 A. The equation Q = I * t is applied, leading to a total current of 2.2 A over a minute, resulting in a calculated charge of 183 C. However, participants question the validity of this calculation due to the differing ammeter readings, suggesting a misunderstanding of current flow in the circuit. The importance of applying Kirchhoff's Current Law is emphasized to clarify how current splits between the meters. Overall, the conversation highlights the need for careful analysis of circuit configurations and current measurements.
Kofyebs
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Homework Statement


Ammeter shows 1.2 A and 1.0 A. How large amount of charge passing through the lamp in 1 minute?
https://physicsforums-bernhardtmediall.netdna-ssl.com/data/attachments/84/84982-6e293679b3592fb475f0f9cac697526f.jpg

Homework Equations


Q=I*t[/B]

The Attempt at a Solution


I = 1.2 + 1.0 = 2.2
t = 1 * 60 = 60
Q = I*t

= 2.2 * 60 = 183 C[/B]
 

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Are you sure the current through the lamp is 2.2A?
 
cnh1995 said:
Are you sure the current through the lamp is 2.2A?
That's why I'm here for help.
 
  • Like
Likes Delta2
Kofyebs said:
That's why I'm here for help.
Why do you think the meters show different currents?
 
cnh1995 said:
Why do you think the meters show different currents?
Cuz they have different currents.
 
Kofyebs said:
Cuz they have different currents.
One meter shows 1.2A and other shows 1A. Where does the remaining current go?
 
cnh1995 said:
One meter shows 1.2A and other shows 1A. Where does the remaining current go?
I don't know. That's the question I got from my teacher. that's why I'm here for solutions.
 
Kofyebs said:
I don't know. That's the question I got from my teacher. that's why I'm here for solutions.
Well, providing direct answers is against the rules here. Helpers will only provide hints. Where do you think the current splits? Which meter will show 1.2A and which one will show 1A? Think on these and previous questions.
 
cnh1995 said:
Well, providing direct answers is against the rules here. Helpers will only provide hints. Where do you think the current splits? Which meter will show 1.2A and which one will show 1A? Think on these and previous questions.
I am here to find out if my equation is correct.
 
  • #10
I am sure you have been taught Kirchoff's Current Law and how to apply it in problems. What do you get if you apply this law at the middle point at the right side of the circuit?
 
  • #11
Kofyebs said:
I am here to find out if my equation is correct.
Q=I*t is always true.
Kofyebs said:
I = 1.2 + 1.0 = 2.2
t = 1 * 60 = 60
Q = I*t

= 2.2 * 60 = 183 C
This is not correct.
 
  • #12
cnh1995 said:
Q=I*t is always true.

This is not correct.
Thanks
 
  • #13
On my tablet computer i can only view one of the images in the original post but...Putting an ammeter in parallel with a lamp as shown in the second image isn't recommended.
 

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