Recent content by icedragon

Yep I used the quadratic formula. Thanks for your help. :)

Thanks for the help. Got the equation in the form (1/f)s^2 - (L/f)s + L = 0 giving the solutions s= (L±sqrt((L/f)^2 - (4L/f))/2 Does that look good? Lecturer hasn't published answers to this problem sheet for some reason. :(

Homework Statement Hi all. This is a problem from one of the problem sheets from earlier in the term. I'm just revising for my exam tomorrow and can't solve this one. Here it is: Consider a light source placed at a fixed distance L from a screen, such that a lens of focal length f can be...

I see, then what's wrong with the equation? I've spent about 6 hours on this question now. I have tried to express the mass of the composite particle in terms of m_0 and then substitute into the energy equation but I just can't get a sensible answer out :/. And it's due in in 2 hours!

Ahh bugger me I completely forgot to include the energy of the stationary particle! Will have a go at it and report back.

I had a feeling that was too simple to be true, thanks. I went through it again this time with (m_0 + m_1) instead of 2m_0 and that gave me the final velocity equal to the initial velocity which can't be right? Am I missing something here? EDIT: In the equation you quoted?

Do you mean that the equation should be rest mass not mass? If so, the rest mass is given as m_0 but yeah I should have written it out fully. Nope I don't know 4-vectors. This is a coursework assignment and at this stage we haven't covered all the material so I am guessing I am supposed to solve...

Homework Statement A particle of rest mass m0 moving at a speed of 3/4 c collides with a same-mass particle at rest and they stick together to form a composite particle. What is the rest mass of the composite particle and what is its speed? Homework Equations E = \gamma mc^2 p = \gamma mu...

Homework Statement What is the apparent magnitude of a 100W light bulb at a distance of 3 m? [Hint: Compare with the Sun to eliminate the unknown constant in the expression relating flux density to apparent magnitude.] . The solar luminosity is L \approx 4 \times 10^{26} W. . The Earth-Sun...