Recent content by sanado

Hi, was just hoping that you could clear up a mis-understanding i have: In a frequency response curve, the y-axis is a decibel scale. Is this a comparison of the microphones response to the reference sound in relation to sound intensity. eg. If the microphone has a +5 db for a particular...

Perhaps it may be easier if i post the question that has sparked my confusion: A science student connects a dynamic loudspeaker to a low voltage AC power pack in an Australian school. The loudspeaker sends sound waves directly towards a concrete wall 3.0 metres away. Take 340 ms-1 as the...

Well if that's the case for them traveling in the same direction, they should change shouldn't they? Does this mean that anti-nodes are now located at 0 and wavelength/2?

Hey guys, was hoping you could help me with a sound question. When sound is emitted from a speaker and it strikes a wall, it rebounds. Since both waves are in phase, a standing wave is created. Are nodes located at wavelength/2, 3wavelength/4? If not, where is there location?

Hey guys, am studying light and matter at the moment. Was just wondering: 1. Assuming an atom requires 3.2 eV to transfer an electron to an excited state, if a photon of 3.3eV struck the atom, would it still be absorbed. If so, what happens to the remaining energy

Hey guys, was wondering if you could help me with this question: What determines the brightness of a lightbulb? I think it would be power (and therefor voltage and current since P = VI) as power is used in the measurement of energy delivered. Why is it the case then that, from the...

What would happen if u had a circuit that was earthed at a point and it had an EMF of let's say 9V. If i had 1 resistor and immediately after that i had a resistor and diode in parallel, would any current enter the resistor. My understand is that it wouldn't since once the diode opens up, it...

But what about a solar cell, isn't that a photodiode in forward bias? Doesnt that produce a voltage/

Just thought i would ask, when a photodiode is acting in reverse bias, it allows current to pass but does not generate voltage. In fact, it has a voltage drop. When in forward bias, it allows current to pass but also generates an EMF. Is this correct, any response would be appreciated.

Okay, so before it enters the final capacitor, would the graph look like a simple straight line, due to clipping. Since this straight line is infact a DC voltage (it doesn't vary) due to the clipping, it is removed by the capacitor and as such, the V out is zero. Is that right?

Okay, that makes sense. So the capacitor acts as a voltage source and this is the reason why the voltage can drop below 0 (the Earth V)?

The question being referred to is question 3 on page 8: http://www.itute.com/physicsline/phys_trial_exam1_2008v2.pdf Answer referred to is Question 3 Area of Study 2: http://www.itute.com/physicsline/phys_trial_exam1_2008v2sol.pdf I don't understand why they get this answer. The answer I...

After studying amplifiers and their operation, i suddenly realized today that i don't really know how they work at all. Assume Vcc = 6V for an NPN transistor, biased correctly to fluctuate about 3V In the Vout, once the DC part has been removed, how can the voltage possibly go lower than...

What is the purpose of placing a limiting resistor infront of an LED?

Is it the voltage divider and/or the Rc resistor that is responsible for biasing an NPN transistor. I am aware the role each play, but was just wondering which part actually biased the transistor, i wouldve thought both?