Recent content by Magma828

How on Earth do wind farms work then? Do they just have a complex gearbox that has to be continuously adjusted?

What exactly do you mean by 'dependent on resources'?

I'm thinking of making an electricity generator which is rotated by hand, or possibly something like wind, or gerbils on a treadmill etc etc.. Anyway, the current and emf produced would vary depending on the velocity at which the generator is turned, correct? I therefore need a way of keeping...

That's basically all the question says. It could possibly be something from the old spec, where the textbook would define exactly what a filter does. I just thought there might be a convention or something.

I'm doing a question about a laser which emits blue and green light. It asks about the light after it has passed through 'a green filter'. What passes through, green or blue light? I originally thought green light must pass through, then realized it could mean green light is reflected.

Ahh okay thanks a lot guys! :D

I'm doing OCR A-Level Physics, and in my textbook it states "They (Penzias and Wilson) made a calculation to find the temperature of the source of the radio waves, which had a maximum intensity at wavelength 1.1 cm, and found it to be 2.7K". This was all good and well, until I answered a...

Um.. is it the time taken for the current to change direction or something like that? Or loss of magnetic flux? I'm a bit lost now :P

I guess the resistance of the coil would increase, and there would also be greater magnetic flux linkage. A higher magnetic flux linkage = a higher induced emf, but according to the (simple) theory I know, only the ratio matters when you do it for two coils.

I need to know the purpose of using different numbers of coil turns for the primary and secondary coils on a transformer, provided the turns ratio remains constant. Put into context, what is the difference between a transformer with 10 turns on the primary, 20 turns on the secondary and a...

I've searched for this question on these forums and google and everyone seems to have the same question as me, but hasn't stated it clear enough for people to understand exactly what they want to know. I'm wondering how long it takes for electricity to turn something on. I don't want to know...

Does that mean that my solution is correct then? I think I've done what you said there: Calculating the total surface area of the sphere in which the detector could potentially be in is: 4 pi r^2 = 4 x 3.14 x 0.16^2 = 0.32m^2 If this surface area was full of detectors, the counts recorded...

Okay this question is in a section of my textbook that has no equations, apart from the slightly mathematical statement: The rate at which a source emits radioactive particles is called its activity, A. An activity of one particle emitted per second is called a becquerel, Bq. Here's the...

x+y=60 x2 = 0.25 y2 find x and y it's part of a massive physics question, and i'll post the whole thing and my workings so far if it turns out that this maths question is impossible.

That's what I thought, but it's strange that they gave the number of the capsules. Probably just to confuse us!