Charged Wire in Uniform Field
About points...
We associate a certain number of points with each exercise.
When you click an exercise into a collection, this number will be taken as points for the exercise, kind of "by default".
But once the exercise is on the collection, you can edit the number of points for the exercise in the collection independently, without any effect on "points by default" as represented by the number here.
That being said... How many "default points" should you associate with an exercise upon creation?
As with difficulty, there is no straight forward and generally accepted way.
But as a guideline, we tend to give as many points by default as there are mathematical steps to do in the exercise.
Again, very vague... But the number should kind of represent the "work" required.
When you click an exercise into a collection, this number will be taken as points for the exercise, kind of "by default".
But once the exercise is on the collection, you can edit the number of points for the exercise in the collection independently, without any effect on "points by default" as represented by the number here.
That being said... How many "default points" should you associate with an exercise upon creation?
As with difficulty, there is no straight forward and generally accepted way.
But as a guideline, we tend to give as many points by default as there are mathematical steps to do in the exercise.
Again, very vague... But the number should kind of represent the "work" required.
About difficulty...
We associate a certain difficulty with each exercise.
When you click an exercise into a collection, this number will be taken as difficulty for the exercise, kind of "by default".
But once the exercise is on the collection, you can edit its difficulty in the collection independently, without any effect on the "difficulty by default" here.
Why we use chess pieces? Well... we like chess, we like playing around with \(\LaTeX\)-fonts, we wanted symbols that need less space than six stars in a table-column... But in your layouts, you are of course free to indicate the difficulty of the exercise the way you want.
That being said... How "difficult" is an exercise? It depends on many factors, like what was being taught etc.
In physics exercises, we try to follow this pattern:
Level 1 - One formula (one you would find in a reference book) is enough to solve the exercise. Example exercise
Level 2 - Two formulas are needed, it's possible to compute an "in-between" solution, i.e. no algebraic equation needed. Example exercise
Level 3 - "Chain-computations" like on level 2, but 3+ calculations. Still, no equations, i.e. you are not forced to solve it in an algebraic manner. Example exercise
Level 4 - Exercise needs to be solved by algebraic equations, not possible to calculate numerical "in-between" results. Example exercise
Level 5 -
Level 6 -
When you click an exercise into a collection, this number will be taken as difficulty for the exercise, kind of "by default".
But once the exercise is on the collection, you can edit its difficulty in the collection independently, without any effect on the "difficulty by default" here.
Why we use chess pieces? Well... we like chess, we like playing around with \(\LaTeX\)-fonts, we wanted symbols that need less space than six stars in a table-column... But in your layouts, you are of course free to indicate the difficulty of the exercise the way you want.
That being said... How "difficult" is an exercise? It depends on many factors, like what was being taught etc.
In physics exercises, we try to follow this pattern:
Level 1 - One formula (one you would find in a reference book) is enough to solve the exercise. Example exercise
Level 2 - Two formulas are needed, it's possible to compute an "in-between" solution, i.e. no algebraic equation needed. Example exercise
Level 3 - "Chain-computations" like on level 2, but 3+ calculations. Still, no equations, i.e. you are not forced to solve it in an algebraic manner. Example exercise
Level 4 - Exercise needs to be solved by algebraic equations, not possible to calculate numerical "in-between" results. Example exercise
Level 5 -
Level 6 -
Question
Solution
Short
Video
\(\LaTeX\)
No explanation / solution video to this exercise has yet been created.
Visit our YouTube-Channel to see solutions to other exercises.
Don't forget to subscribe to our channel, like the videos and leave comments!
Visit our YouTube-Channel to see solutions to other exercises.
Don't forget to subscribe to our channel, like the videos and leave comments!
Exercise:
A charged wire is placed in a uniform electric field. center includegraphicswidthcm#image_path:chargin-uniform-field-# center abcliste abc Derive a formal expression for the force acting on the wire. abc Calculate the magnitude of the force on a wire with charge QO in a field with strength EO. What is the direction of the force? abcliste
Solution:
abcliste abc Since the electric field is uniform the distribution of the charge along the wire does not matter. This means we can treat the charge like a po charge. Hence the force on the wire is F_E FformF For a more rigorous proof we split up the wire o N short segments of length textdell. If the segments are short enough we can consider them to be po charges. The force on segment i is therefore F_i q_i E where q_i is the charge of segment i i dots N. The total force on the wire is then F_E _i^N F_i _i^N q_i E labeleq: E _i^N q_i E Q where Q _i^N q_i is the total charge of the wire. vspacemm Remark: For infinitely small segments textdell to refeq: becomes F_E _^ell E fracQell textdell E _^ell lambdatextdell E lambda _^ell textdell E lambda ell E Q The result is correct for an arbitrary charge distribution in the wire i.e. it does not have to be uniform. abc The magnitude of the force is F_E FF absQtimesE F approx resultFP- Since the charge is negative the force pos in the opposite direction of the field lines. abcliste
A charged wire is placed in a uniform electric field. center includegraphicswidthcm#image_path:chargin-uniform-field-# center abcliste abc Derive a formal expression for the force acting on the wire. abc Calculate the magnitude of the force on a wire with charge QO in a field with strength EO. What is the direction of the force? abcliste
Solution:
abcliste abc Since the electric field is uniform the distribution of the charge along the wire does not matter. This means we can treat the charge like a po charge. Hence the force on the wire is F_E FformF For a more rigorous proof we split up the wire o N short segments of length textdell. If the segments are short enough we can consider them to be po charges. The force on segment i is therefore F_i q_i E where q_i is the charge of segment i i dots N. The total force on the wire is then F_E _i^N F_i _i^N q_i E labeleq: E _i^N q_i E Q where Q _i^N q_i is the total charge of the wire. vspacemm Remark: For infinitely small segments textdell to refeq: becomes F_E _^ell E fracQell textdell E _^ell lambdatextdell E lambda _^ell textdell E lambda ell E Q The result is correct for an arbitrary charge distribution in the wire i.e. it does not have to be uniform. abc The magnitude of the force is F_E FF absQtimesE F approx resultFP- Since the charge is negative the force pos in the opposite direction of the field lines. abcliste
Meta Information
Exercise:
A charged wire is placed in a uniform electric field. center includegraphicswidthcm#image_path:chargin-uniform-field-# center abcliste abc Derive a formal expression for the force acting on the wire. abc Calculate the magnitude of the force on a wire with charge QO in a field with strength EO. What is the direction of the force? abcliste
Solution:
abcliste abc Since the electric field is uniform the distribution of the charge along the wire does not matter. This means we can treat the charge like a po charge. Hence the force on the wire is F_E FformF For a more rigorous proof we split up the wire o N short segments of length textdell. If the segments are short enough we can consider them to be po charges. The force on segment i is therefore F_i q_i E where q_i is the charge of segment i i dots N. The total force on the wire is then F_E _i^N F_i _i^N q_i E labeleq: E _i^N q_i E Q where Q _i^N q_i is the total charge of the wire. vspacemm Remark: For infinitely small segments textdell to refeq: becomes F_E _^ell E fracQell textdell E _^ell lambdatextdell E lambda _^ell textdell E lambda ell E Q The result is correct for an arbitrary charge distribution in the wire i.e. it does not have to be uniform. abc The magnitude of the force is F_E FF absQtimesE F approx resultFP- Since the charge is negative the force pos in the opposite direction of the field lines. abcliste
A charged wire is placed in a uniform electric field. center includegraphicswidthcm#image_path:chargin-uniform-field-# center abcliste abc Derive a formal expression for the force acting on the wire. abc Calculate the magnitude of the force on a wire with charge QO in a field with strength EO. What is the direction of the force? abcliste
Solution:
abcliste abc Since the electric field is uniform the distribution of the charge along the wire does not matter. This means we can treat the charge like a po charge. Hence the force on the wire is F_E FformF For a more rigorous proof we split up the wire o N short segments of length textdell. If the segments are short enough we can consider them to be po charges. The force on segment i is therefore F_i q_i E where q_i is the charge of segment i i dots N. The total force on the wire is then F_E _i^N F_i _i^N q_i E labeleq: E _i^N q_i E Q where Q _i^N q_i is the total charge of the wire. vspacemm Remark: For infinitely small segments textdell to refeq: becomes F_E _^ell E fracQell textdell E _^ell lambdatextdell E lambda _^ell textdell E lambda ell E Q The result is correct for an arbitrary charge distribution in the wire i.e. it does not have to be uniform. abc The magnitude of the force is F_E FF absQtimesE F approx resultFP- Since the charge is negative the force pos in the opposite direction of the field lines. abcliste
Contained in these collections:

