Higher Physics

Electricity and Electronics - Activity 3

e.m.f. and internal resistance with parallel circuits

Aim - To determine the internal resistance of a battery     Instructions
        Click on a lamp to screw it in or unscrew it.
  • Note the current I and the corresponding t.p.d. V values when no lamps are screwed in.
  • Repeat the above for each case as one, then two, then three lamps are screwed in.
  • Using Ohm's Law, copy and complete the final column of the table by calculating the value of the internal resistance of the battery.
No. of lamps lit Current I  (A) t.p.d. V  (V) "lost volts"  (V) internal resistance (W)
0        
1        
2        
3        
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