If the power is out, the window might be stuck in the down position. You may be able to manually *close* it in some car models by using a tool to carefully engage the mechanism, but this is extremely model-specific and usually requires removing interior panels and potentially damaging them. It's not something to attempt lightly.
Instead of trying to force it, your best bet is:
* Check the fuses: A blown fuse could be the problem. Check your car's owner's manual to locate the fuse box and identify the fuse for the power windows.
* Check the power window switch: Try using the driver's side switch to operate the passenger window. A faulty switch on the passenger side could be the issue.
* Call a professional: If neither of these solves the problem, you should contact a mechanic or your dealership. Attempting to manually force the window could cause further damage.