# I don't understand the conversion from eV/c to kg*m/s

Watch
Announcements
#1
Hi, so I understand that when you divide energy by the speed of light, c, you get momentum, and that's how the units eV/c come about. I get that 1 eV/c = 5.36 x 10^-28 kg*m/s by multiplying by 1.6 x 10^-19 J/eV and dividing by 3 x 10^8 m/s. I'm just struggling to understand how the units work, as the multiplication by 1.6 x 10^-19 J/eV would convert the units into J/c, but then wouldn't multiplication by c turn the units back into units of energy? Except they are still units of momentum- I just can't see how the conversion makes the units equivalent to kg*m/s.
0
5 years ago
#2
E = MC^2
E = PC (P is momentum)

MC^2 = PC

P= MC (units kg*ms^(-1))
0
X

new posts
Back
to top
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### Poll

Join the discussion

#### Current uni students - are you thinking of dropping out of university?

Yes, I'm seriously considering dropping out (99)
13.45%
I'm not sure (32)
4.35%
No, I'm going to stick it out for now (230)
31.25%
I have already dropped out (17)
2.31%
I'm not a current university student (358)
48.64%