Question

A ΔV = 1.7 V battery loses E = 5.5 J of

energy each day (t = 24 hrs) powering a cell phone.
a) Input an expression for the average current, I,
supplied to the phone.

Answer 1

The average current supplied to the phone by a 1.7 V battery that loses 5.5 J of energy each day is approximately 37.44 μA.

Step-by-step explanation:

To find the average current, I, supplied to a cell phone by a battery with a ΔV = 1.7 V voltage that loses E = 5.5 J of energy each day (t = 24 hrs), we can use the relationship between power (P), voltage (V), and current (I): P = VI. Now, power is also the rate of energy consumption, so if a battery loses 5.5 J of energy in 24 hours, we can express this as P = 5.5 J / (24 × 3600 s). From this, we can calculate the power as P = 5.5 J / 86400 s = 6.365× 10-5 W.

Next, we use the expression for power involving current and voltage to find the average current:

P = VI → I = P / V = (6.365× 10-5) W / 1.7 V = 3.744× 10-5 A.

Thus, the average current I that the battery supplies to the phone is approximately 3.744× 10-5 A or 37.44 μA.