Recent content by Reptic

no, should be kelvin 293 right?

Homework Statement Air at 20C is compressed adiabetically from 1 bar to 10 bar. What will its temperature be? Homework Equations pV = nRT, P1P2=T1T2 P1Vλ1=P2V2λ The Attempt at a Solution In picture...[/B]

Thank you so much for that. I look forward to using that in the future...

hahaha put it like that and nothing seems easier so the answer is just 2f or 110 so to express it in the answer i would say something like 1/f = 1/v + 1/u ∴ 1/f = 1/v + 1/v = 2/v 1/f = 2/v 1 = 2f/v v = 2f

v = 2 x 1/55?

2/v

1/f = 1/v + 1/u 1/55 = 0.5 x 1/55 + 0.5 x 1/55 0.0181 = 0.009 + 0.009 0.009 = Approx 111 mm??

Im afraid i am now completely lost: Very little, in fact nothing I don't see how interchanging the values of v or u makes a change if they're the same. Then even if i do i don't know how to put them into an equation that gets me towards the correct result.

Hi thanks for your reply! I wasn't sure about the last one, thought it might be relevant as it says that object height and image height is the same as image and object distance...i guess not If m is 1 then would that mean that u and v need to equal 1 to find the answer...i don't know how to...

Homework Statement At what distance from an object must a 55mm camera lens be placed if the image is to be the same size as the object? Homework Equations 1/u + 1/v = 1/f m = v/u do/di = ho/hiThe Attempt at a Solution My thinking is that (m) needs to equal 0 therefore v/u needs to equal...