iso. to img.

don't know if this is the right place to post this please move if it is? when i run the sudo dd command in terminal to change a ubuntu.iso into an img so i can boot it from a flash drive it gives me a permission denied

here's the command

brian-andersens-MacBook-Pro:~ brianandersen$ sudo dd if=/Users/brianandersen/Desktop/untitled.img.dmg of=/dev/rdisk2 bs=1m

here's the result
dd: /dev/rdisk2: Permission denied

im using the right password i've checked it.

Is virtual machine is the same as a multi boot? Thats what i'm trying to do. I've tried that but it won't find it when i alt boot. So i looked on the ubuntu website and thats what it says to do if you want to install from a flashdrive.

oic im going to use bootcamp based on the speed difference vm has. Yeah it's formatted mac os extended journaled(extended) and everythings read/write except everyone which is read only

lol i got it to work. I was using disk 2 but i formatted my disk earlier and that changed it to disk 1 all i had to do was change that. sry bro thanx for the help and at least i know the difference between vm and bootcamp now