Recent content by Energize

The max resolution of a simple optical scanner is half the wavelength though is it not? Giving a max resolution of 200nm and average of 275nm? How does one determine the max resolution of say a graphite drawing, I assume it is related the size of the graphite molecules?

May seem like a bizarre question but I was wondering what the maximum possible resolution of a scanned A4 image would be. A4 paper is 0.297m x 0.21m, average resolution of light is 200nm. So I get, (0.297m / 200x10^-9m) x (0.21m / 200x10^-9m) = 1.56 terapixels Is this about right...

What equations would I need for calculating this, say if I wanted to know what the power/intensity of an x watt, x wavelength laser would be reduced to after x metres?

You forgot to add the specific latent heat of fusion. I don't have a clue what those are. :P

How do I work out the rate of heat transfer between different states of matter? Say for example I wanted to calculate how long it takes for a freezer at -15 degrees to freeze 30g of water in a cup at 10 degrees, what equations would I need to use? I've already worked out that 11,274 joules...

What if the magnet was facing the other way?

If you have a bar magnet in a coil and rotate it sideways (poles on the side of the magnet) does it produce an alternating current and do the number of turns in the coil affect this, and if you move a magnet through a coil one way and then the other, does it produce an ac current?

In school yesterday I was doing a practical and when I moved a small 1.5T block magnet near a rheostat the magnet started vibrating, why does it do this?

If you combine many small magnets together in a cube or spherical shape (say those 1.5 tesla rare Earth magnets), is the resulting magnetic field able to affect even heavier objects, or is there no difference in the range/energy of the field?

What does the "." in equations stand for? I've been revising electric fields, and have come across the equation \Delta E_{p} = k . Q_{1} Q_{2} [ \frac{1}{r_{1}} - \frac{1}{r_{2}}] I have never come across a decimal point in an equation before, what does it mean?

Is it possible a microscope like this could be created in the future though, for looking at things in more detail than an electron microscope albeit for a very short time before they became too damaged, perhaps even individual atoms? Also, do the electrons act as beta radiation and damage the...

I noticed that websites usually say that the maximum effective magnification of a light microscope is 2000x, so electron microscopes are used for greater resolution due to their shorter wavelength, but don't photons in the gamma ray range have an even shorter wavelength, allowing them to see...

What would be observed if you were orbiting the earth?

If you were traveling near the speed of light on a spacecraft moving away from the Earth how you would you observe events happening on the earth, at normal speed or in slow motion? I can't work this out because I know light is always gaining on you at C even if you are traveling close to the...

I have to explain the argument, why the centripetal force must be radial and towards the centre, rather than away. I have just started circular motion and have no idea how to explain this sort of thing, I don't even understand the question!