If you examine your smartphone battery, you will likely see two numbers: the bat

Question

If you examine your smartphone battery, you will likely see two numbers: the battery's "capacity" labeled in mAh (milliamps × hours or milliamp-hours), and the battery's voltage or potential difference in V (volts).

1. What physical quantity is the battery's "capacity" measuring? Explain how you can tell. T

2. Suppose your phone's battery has a capacity of 2900 mAh and a potential difference of 3.5 V. What is the amount of charge, in C (coulombs), that is stored in your smartphone battery when it's fully charged? Charge = C

3. Smartphone chargers are usually labeled with their current output in A (amps). Suppose your charger delivers a current of 1.1 A. If your phone's battery is completely drained, how long will it take to fully charge the battery using your charger? Charging time = hours

4. Smartphones are advertised with a certain amount of "talk time", i.e., how long the phone's battery will last if you are making a call. If your phone is advertised with 24 hours of talk time, what is the average current coming from your phone's battery while making the call? Average current = A

5. What is the average power output of your phone's battery while you're making a call? Average power = W

Explanation / Answer

1. it labbeled how much charge battery can provide.

2. C = (2900 x 10^-3 C / s) (3600 s)

= 10440 C

3. t = (10440)/1.1 = 9490.9 sec

t = 2.64 hrs

4. I = (10440)/(24 x 3600s) =0.121 A

5. Energy = (2900 x 10^-3 J/s)(3600 s) (3.5 V) = 36540 J

Power = 36540 / (24 x 3600) = 0.423 W

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.