Rear tire dragging on rim brake arm
It looks like your new brake pads have pushed the right brake arm out moving the top of the arm down, touching the tire. You need the top of the brake arm to move up and give you some clearance.  

Options


Get thinner brake pads
Cut the new brake pad down some so that it will be thinner
If there are any washers between the back of the brake pad and the brake arm remove them (I can't tell from the picture)


Hopefully all you need to do is remove some washers.