No, a wireless phone will not function during a power outages. This is because although wireless phones have their own battery power, the phone base that transmits its signal to the wireless phone will not work during a power outage.

wireless. but it depends on the power of the controller for each device.

Unless somebody stole them from you then yes a wireless router does have cords. You have the power cord which connects the power to the device and you have the Ethernet cables which are used to connect the wireless router to the modem and to any other hard-wired devices.

The power supply that is needed for a wireless microphone would be a rechargeable battery. Batteries such as these could be purchased at Amazon or Full Compass.

No, he simply created lots of local "artificial lightning".

Tesla died penniless in 1943 after having spent his money and time on a variety of wireless communication and wireless power systems that never performed as he wanted.