# What is this unit?

1. Dec 29, 2011

### iphilosopher

Change the forum if this is in the wrong place but I was doing some math (multiplying hertz and watts) and I came with 4.8912 × 10^12 m^2 kg / s^4, I don't know what unit that is, so can anybody tell me if there even is one?

2. Dec 29, 2011

### Dickfore

there is no known physical quantity with those dimensions.

3. Dec 29, 2011

### Staff: Mentor

$$Watt = Joule/s = kg*m^2*s^{-3}$$

$$Hertz = s^{-1}$$

So your units are correct. Basically it's Joules per s^2, or Watts per second.

But as pointed out, it is unusual to multiply power and frequency. What was the calculation for?

4. Dec 30, 2011

### iphilosopher

I meant to divide hertz and watts and I would get 2 122.91667 m^-2 * kg^-1 * s^2 so now I think my question truly is what is that unit

5. Dec 30, 2011

### Staff: Mentor

As asked, what are you trying to accomplish? It almost seems like you are doing blind math, hoping to stumble on something interesting.

Last edited by a moderator: Dec 30, 2011
6. Jan 1, 2012

### iphilosopher

I was trying to find how far one photon can go like with a radio transmitter, how far could one of those photons could go. And now I found I did not have enough information to do these calculations.

7. Jan 2, 2012

### Antiphon

There's no limit to how far a photon can go. But I'm not sure you can come to a conclusion like that by doing dimensional analysis. Sometimes interesting things can pop out though.