## Due before class Monday, Jul 9th

Physics 106, Summer 2012

Did you complete the reading assignment?

Yes
No

Did you complete the entire quiz or spend at least 15 minutes working on this quiz and the attached links?
Yes
No

## KEY CONCEPTS:

1) A magnetic force is created when a charge or a charged object is moving through a magnetic field.

2) A magnetic field is induced by a current carrying wire.

3) The direction of magnetic forces and fields are determined by the right hand rule.

Electricity and magnetism cannot accurately be separated into to distinct entities. They are actually the same, manifested in different ways. To be accurate in your description of them, you really need to combine them and call it electromagnetism. That is why when a charge moves through a magnetic field it experiences a magnetic force. It is also why when current is moving through a wire it creates a magnetic field around the wire.

Go to the following applet: http://surendranath.tripod.com/Applets/Electricity/MovChgMag/MCM.html and click on the black box to start it.

The Xs and Os show the direction of the magnetic field at that position. An X means the direction of the magnetic field is into the page and an O means the direction of the magnetic field is out of the page. The green arrow indicates the magnetic force on the charge and the black arrow indicates the velocity of the charge.

What happens to the magnetic force on the charge when the velocity increases?

Increases
Decreases
Stays the same

What happens to the magnetic force on the charge when the magnetic field strength increases in magnitude?

Increases
Decreases
Stays the same

What happens to the magnetic force on the charge when the mass of the charge increases?

Increases
Decreases
Stays the same

Why does the trajectory of the charge change so much when the mass of the charge is changed?

Under what condition can a charge move through a magnetic field and not experience a magnetic force?

Why does the charge suddenly change its path when crossing the boundary from a magnetic field going into the page to a magnetic field going out of the page?

Is the charge in the applet a positive or negative charge?

Positive
Negative

What would change about the trajectory of an identical but opposite charge?

FEEDBACK

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1) If you have a specific question or concern and would like an individual answer you will need to come by the office or send an email.
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Was there anything that you didn't understand in the reading assignment?  What was confusing to you?