Conceptual Questions Lenz's Law, Solenoid

AI Thread Summary
The discussion revolves around understanding Lenz's Law and its application to a solenoid with a wire loop inside. When the voltage applied to the solenoid increases, the magnetic field inside the solenoid points to the right, which influences the induced current in the loop. The correct answer to the first question is that the induced current at location A points out of the paper, opposing the increase in magnetic flux. For the second question, the torque on the loop is directed out of the paper due to the orientation of the magnetic dipole moment. The participants emphasize the importance of applying the right-hand rule and Lenz's Law to determine the correct answers.
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Homework Statement



https://www.dropbox.com/s/17hsoz0zdfoston/Screen shot 2013-05-10 at 12.37.44 PM.png

1) A voltage is applied to a solenoid such that a current is flowing in the indicated direction. Inside the solenoid is a single wire loop that is oriented in the same direction as the solenoid windings.

Which one of the following statements is true in the case where the voltage applied to the solenoid is increased?
a) The magnetic field of the solenoid points to the left while the induced current at location A points out of the paper.
b) The magnetic field of the solenoid points to the right while the induced current at location A points into the paper.
c) The magnetic field of the solenoid points to the left while the induced current at location A points into the paper.
d) The magnetic field of the solenoid points to the right while the induced current at location A points out of the paper.

2) Which one of the following statements is true in the case where the voltage applied to the solenoid is increased?
a) The magnetic dipole moment of the loop points to the right.
b) The torque on the loop points into the paper.
c) The torque on the loop points out of the paper.
d) The magnetic dipole moment of the loop points to the left.
e) A voltage is only induced in the inner loop, not in the solenoid itself.

Homework Equations



Lenz's law

The Attempt at a Solution



I thought the answer to question 1 was c) since the magnetic field would point in the opposite direction to fight the increase in magnetic flux, but it was wrong. I have no idea where to start for the second question. Thanks in advance!
 
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A to part 1, wrap your hand around the wire around the solonoid. Where do the fingers point?
 
To the right. I know how to use the right hand rule, but in this situation I am confused with the loop inside the solenoid. The magnetic field inside the solenoid points to the right, but how does that affects the current inside the loop? Would the current at location A point outside the paper?
 
What does Lenz law state? Something like the current would oppose the change in the field?
 
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