Recent content by heth

Sorry - wasn't on the forum for a couple of days. What I was trying to allude to is that when you're calculating the energy (or escape velocity) required to escape to infinity from, say, the Earth's surface, the fact that the force drops off with distance means that you don't require an infinite...

I think that the second sentence may be refer to scalar quantities such as temperature, where you can have +10'C but also -10'C. In a case like this, the signs don't declare the "direction" of the temperature - just its value on a scale with reference to an agreed zero point.

Precursor> What do you know about inverse square laws? This might help.

Wilbur and Orville Wright - the Wright brothers.

You could make yourself a ramp and try this? OK so you couldn't do that in an exam, but it'll give you a better feel for what's going on, and improve your intuition for similar problems in the future.

What's your gut feeling? Do you think it would be conserved, or wouldn't be conserved?

> am i wright. You certainly are, Wilbur! The dark patches will be halfway between the light patches - so if you imagine/sketch the fringes then count along, you'll get m=4.5 for the 5th dark patch.

The units for your grating are "lines per cm". Just like the units for the fence are "posts per m". No mention of area at all in the problem. If you work out how to calculate the distance between the posts (which is easier to imagine than lines you can't really see) then you can use the same...

It's now possible to browse most of the book via the O'Reilly site and Google books: http://oreilly.com/catalog/9780596102371/preview

What do you think? How far have you got?

The link to your earlier post isn't working. Did you list relevant equations and show an attempt at a solution when you originally posted this problem?

A lot of problems involve conservation of physical quantities. What might be conserved here?

Think about it in terms of energy conservation. Do a sketch of the system at the start and at the end of the period you're interested in. Then play spot the difference. Where has energy been transferred?

Imagine a little fence which is constructed with four fence posts per meter. What is the spacing between the posts? That should help you with the meaning of "6000 lines/cm".

What are all the possible digits that could appear in a hexadecimal number? (For example, the possible digits in a binary number are 1 and 0.) If you're not sure, look it up in a book or online. That should help you figure it out.