# Electricity Calculation. I=Q/t

## 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 [Broken]

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]

#### Attachments

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## Answers and Replies

cnh1995
Homework Helper
Gold Member
Are you sure the current through the lamp is 2.2A?

Are you sure the current through the lamp is 2.2A?
That's why I'm here for help.

• Delta2
cnh1995
Homework Helper
Gold Member
That's why I'm here for help.
Why do you think the meters show different currents?

Why do you think the meters show different currents?
Cuz they have different currents.

cnh1995
Homework Helper
Gold Member
Cuz they have different currents.
One meter shows 1.2A and other shows 1A. Where does the remaining current go?

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.

cnh1995
Homework Helper
Gold Member
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.

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.

Delta2
Homework Helper
Gold Member
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?

cnh1995
Homework Helper
Gold Member
I am here to find out if my equation is correct.
Q=I*t is always true.
I = 1.2 + 1.0 = 2.2
t = 1 * 60 = 60
Q = I*t

= 2.2 * 60 = 183 C
This is not correct.

Q=I*t is always true.

This is not correct.
Thanks

CWatters
Science Advisor
Homework Helper
Gold Member
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.