ECE112 
Current Charge and Voltage Problems      

Note: The assumption is that the appliance or device operates until the last coulomb 
      is used. 

3. As a joke, your wisecracking buddy shorts out your spare pacemaker battery 
   by placing a paper clip across the battery terminals for 10 minutes. While 
   shorted, 150mA of current flows through the paper clip. The battery manufacturer 
   claims that their batteries can deliver 1mA for 200 hours. The pacemaker draws 
   50uA while operating. 
   a)How much (in percentage) of the initial charge is left in the battery after 
     the prank? 
   b)If the spare pacemaker battery is installed, how many days do you have 
     before the ambulance arrives for you? 
   Ans: 87.5%, 145 days