# Hello all

1. Jan 23, 2005

### hype_chicky

a moving particle has a rest mass which is double its kinetic energy. Find its speed and momentum..=)

2. Jan 24, 2005

### vincentchan

this is the most basic problem in relativity.... are you having a hard time understanding relativity or you just can't figure out how to do this problem....
relativity usually puts in a advance physics class. since you are learning relativity now, i believe you have already suffer through the classical mechanic and electrostatic and thermal physics those basic stuff.... and you have already develope a skill to deal with physics problems. This problem is not tricky at all. plug the number in appropiate formulas and the answer will shown up instantly.... if you really can't do this problem, at least show me some of your work or let me know which part you stuck in....

3. Jan 24, 2005

### hype_chicky

okay so the rest mass is doubel the kinetic energy so i have Ek = mc^2/ sqare root 1-V^2/C^2 - mc^2...yet once agnin i DO NOT understand how to fit it in..as u can see physics is not one of my favourite classes =)

4. Jan 24, 2005

### dextercioby

Okay.So its rest mass (mulitplied by c^squared to give energy) is 2 times greater than the KE.Can u write the RHS from this equation?
$$m_{0}c^{2}=2...$$

What should be instead of those points...??

Daniel.