• Congratulations to the Class of 2024 on your results!
    Let us know how you went here
    Got a question about your uni preferences? Ask us here

Photoelectric Intensity Conundrum (1 Viewer)

k02033

Member
Joined
Mar 9, 2006
Messages
239
Location
Parramatta
Gender
Male
HSC
2007
But what k02033 expects of us is to understand all the university style information
which bit do you refer to as "uni style information" that i have presented?

And if i were not to present information in the way that i have, how would you answer questions and fix misconception, say the one proposed by the original poster in this thread and all the other photoelectric threads that i have answered?

including all the mathematics and what not, and to use that information in a test. That's just ridiculous and time wasting.


are you saying using I=nhf in a test would be ridiculous and time wasting? :) i certainly hope not ...
 
Last edited:

youngminii

Banned
Joined
Feb 13, 2008
Messages
2,083
Gender
Male
HSC
2009
k02033 said:
thats not true in a general, intensity is a measurment of how much energy the radiation delivers to the cathode per unit of time per unit of area of the cathode. as an equation you can think of intensity as I=nhf, where n is how many photons lands on the cathode per unit of time per unit of area. So there are 2 ways of increasing the radiation intensity, one is to increases its frequency or increase how many photons are emitted, or a combination of both.

but we all know that the kinetic energy of photoelectrons are only dependent on hf, ie the energy of each individual photon.

If i increase teh frequency of the radiation keeping n constant i can indeed increase intensity I=nhf

but this way of increasing intensity can actually increase photoelectron energy, since i am varying f.

so its only safe to say that changing the intensity of EMR while not varying its frequency will not change the photoelectron energy, but increase current

all these assumes f>fo obviously.
All that does is confuse most people. I had to read that like ten times over to understand it properly.
You're also making it seem as if that's what we should write in our exams, as if we've been taught the wrong thing and if we use that wrong thing in an exam, we'll get no marks.
Make sure that you say it's out of the syllabus, that you're not required to know it and to NOT use it in an exam.

Edit:
k02033 said:
not true, wow there were 2 previous threads on this topic.. and every student keeps saying this..
hsc murdered the definition of intensity
Further illustrates my point. You ARE saying it's wrong and that would lead most people to think "Oh shit I haven't learnt this" etc.
 
Last edited:

k02033

Member
Joined
Mar 9, 2006
Messages
239
Location
Parramatta
Gender
Male
HSC
2007
All that does is confuse most people. I had to read that like ten times over to understand it properly.
Good, you are one of the people who got confused, went to study and learn something new and useful congrats(this is called the process of learning)! you now have an edge over students who havnt learn this,

You're also making it seem as if that's what we should write in our exams
never forced anyone to use it in an exam, but i certainly suggest/hope you do, choice is yourss

as if we've been taught the wrong thing
you have

if we use that wrong thing in an exam, we'll get no marks.
i never said that, stop putting words in my mouth
 
Last edited:

k02033

Member
Joined
Mar 9, 2006
Messages
239
Location
Parramatta
Gender
Male
HSC
2007
Make sure that you say it's out of the syllabus, that you're not required to know it and to NOT use it in an exam.
you dont tell me what to do

Edit:
Further illustrates my point. You ARE saying it's wrong and that would lead most people to think "Oh shit I haven't learnt this" etc.

1st thing you have said thats true. And i hope some of those people take the effort to learn the correct idea just as you did
 
Last edited:

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top