Section 29.2 Electronic Devices

Practice Test
      
  1.In Figure 29-20, what resistor should be used to increase the current to 25 mA? Assume that the potential drop across the LED is still 1.2 V.  
  a.   240 Ω  
  b.   120 Ω  
  c.   300 Ω  
  d.   192 Ω  
  Hint    
      
  2.If the diode connected to ammeter A2 in Figure 29-22 were reversed, what would happen to A2's reading?  
  a.   It would read zero.  
  b.   It would decrease to a non-zero value.  
  c.   It would remain unchanged.  
  d.   It would increase.  
  Hint    
      
  3.If the battery in Figure 29-18 were reversed, which lamp(s) would light?  
  a.   L1 only  
  b.   L2 only  
  c.   neither lamp  
  d.   both lamps  
  Hint    
      
  4.If the diode connected to ammeter A2 in Figure 29-22 were reversed, what would happen to A1's reading?  
  a.   It would remain unchanged.  
  b.   It would read zero.  
  c.   It would increase.  
  d.   It would decrease to a non-zero value.  
  Hint    
      
  5.In Figure 29-17c, how does the current go through the diodes?  
  a.   no current through the top one, to the left for the bottom one  
  b.   to the left for the top one, the right for the bottom one  
  c.   to the right for the top one, no current through the bottom one  
  d.   to the right for the top one, the left for the bottom one  
  Hint    

 
   
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