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What exactly is 'frequency' in the particle model of light? (1 Viewer)
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theodore0307
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Your over thinking it. Frequency is regarding waves. Only when light behaves as a wave it has a frequency
emilios
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how would i answer this question then? i though that if the frequency is above the threshold frequency then only changing the intensity can affect the photocurrent
but apparently changing the frequency also changes the photocurrent
Same power output.
Red light has a smaller frequency than blue light. So red light has less energy per photon. In this case, you need more photons of red light to achieve the same power output as that of blue light. B is the answer.
Red light has a smaller frequency than blue light. So red light has less energy per photon. In this case, you need more photons of red light to achieve the same power output as that of blue light. B is the answer.
Perf answer. Band 6
IR
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No. Quanta have frequency, and thats why you have threshold frequency.
theodore0307
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IR
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Na dw, happens to everyone. Its called 'clouding of consciousness' and medically referred to as delirium, which I can get susceptible to sometimes. Usually for me its because I haven't had the caffeine for few days.
Do remember with these types of questions where you are given that something is the same for both items we are examining, that you will need to work your way around to find out what happens as you start playing around with the constant. There are many many multiple choice questions like this in HSC.
So power is the work done per unit of time. Since both have an equal power output, we shall assume that over a fixed time interval, which is actually already given to you in this case as per second. Sometimes you may not be given a time interval at all and you will have to make an assumption to test the case. Then using E = hf just look at what happens when you increase/decrease the frequency onto the quantity we want, which is the amount of photons per second received.
So yeah do remember to watch out for any assumptions you need to personally make when doing multiple choice questions. Questions like these sometimes do pop up in short answers, and students may tend to struggle with them to quite an extent. If you use your toolkit of understanding physics to tackle the problem in a logical manner, then you'll be fine with these types of questions. Not all these formulas are just an application of equating different quantities to get the right answer. Some intuition into what certain terms such as power, energy, frequency, wavelength, etc can get you further than you think when doing physics. Just my two cents.
So power is the work done per unit of time. Since both have an equal power output, we shall assume that over a fixed time interval, which is actually already given to you in this case as per second. Sometimes you may not be given a time interval at all and you will have to make an assumption to test the case. Then using E = hf just look at what happens when you increase/decrease the frequency onto the quantity we want, which is the amount of photons per second received.
So yeah do remember to watch out for any assumptions you need to personally make when doing multiple choice questions. Questions like these sometimes do pop up in short answers, and students may tend to struggle with them to quite an extent. If you use your toolkit of understanding physics to tackle the problem in a logical manner, then you'll be fine with these types of questions. Not all these formulas are just an application of equating different quantities to get the right answer. Some intuition into what certain terms such as power, energy, frequency, wavelength, etc can get you further than you think when doing physics. Just my two cents.