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You have a 9V battery connected to a device you wish to power. 5C of charge flows out of the battery over the course of twohours. What is the average current (in Amps) the flowed during that time?

2 Answers

6 votes

Answer: 0.00625A

Step-by-step explanation:

Quantity of charge Q flowing in a circuit per time is equal to the product of the current flowing and time take. Mathematically

Q = It... 1

Where Q is the charge, I is the current and t is the time

For a charge across a capacitor, Q = CV... 2

C is the capacitance of the capacitor

V is the voltage

Equating 1 and 2, we have

It = CV

I = CV/t

Given C = 5C, V = 9V and t = 2hrs = 120seconds

I = 5×9/7200

I = 45/7200

I = 0.00625A

Average current that flowed during that time is 0.00625A

User Kevinl
by
3.7k points
3 votes

Answer:

0.00625 A.

Step-by-step explanation:

From Faraday's law of electricity,

Quantity of electric charge = Current × time.

Q = It .................. Equation 1

Where Q = Quantity of charge, I = current, t = time.

Making I the subject of the equation,

I = VQ/t .............. Equation 2

Given: Q = 5 C t = 2 h = (2×3600) s = 7200 s, V = 9 V

I = 5×9/7200

I = 0.00625 A

Hence the average current flowing through = 0.00625 A.

User Bendr
by
3.7k points