Author Question: A transformer for charging a power tool steps the line voltage down to 2.9 V. The output current of ... (Read 86 times)

segrsyd

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A transformer for charging a power tool steps the line voltage down to 2.9 V. The output current of this transformer is 240 mA. If the transformer is 80 efficient, what is the input current?
 
  A)
 
  300 mA
  B)
 
  7.3 mA
  C)
 
  240 mA
  D)
 
  190 mA
  E)
 
  4.6 mA

Question 2

An electron moves with a speed of 3.0  104 m/s perpendicular to a uniform magnetic field of 0.40 T. What is the magnitude of the magnetic force on the electron?
 
  A)
 
  4.8  10-14 N
  B)
 
  1.9  10-15 N
  C)
 
  5  10-20 N
  D)
 
  2.2  10-24 N
  E)
 
  zero



Kimmy

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Answer to Question 1

B

Answer to Question 2

B



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