Question

The power requirement of an electronic portable device is 1.5Amp at 12 volts. What is the minimum number of AA size batteries required for powering this device? Assume one AA battery is capable of supplying up to 1.5 V and 1 Amp of current. Draw a picture of your answer. (Hint: How should these batteries be connected? Series? Parallel? Both?) (4 points)

Answer 1

Answer:

You need at least 8 batteries in order to power your electronic portable device (EPD)

The batteries need to be connected in series.

Explanation (See attachment):

The batteries we are using are rated 1.5V and 1 Amp.

• Voltage => When batteries are connected in series, their voltage adds up. Looking at the drawing, we connected 8 batteries to get up to 12 Volts needed by the EPD.
• Current => The current given is current capacity and real units must be in Ah or Amps-hour, meaning that each battery could supply 1 Amp for one hour before losing charge, or 2 Amps for half an hour. The load on the circuit, in this case the EPD will draw as much current as it needs to work.

A little more explanation about the drawing:

• The drawing on the left shows 8 batteries being connected in series. It also shows a Resistance which is the internal resitance of the system and finally our load which is the electronic portable device (EPD).
• The drawing on the left is just a way of simplifying the circuit. When connecting batteries in series you are creating a cell and that is the symbol for it.
• The bottom drawing is an even simpler version. All you have is a battery that can supply 15V, and you know it is 8 AA batteries connected in series.