Problems with electricity due to old device?

Hello,

I bought an iMac G3 from 1998. The second time I turned it on, it wouldn't turn on again, but I could hear a quiet humming/beeping sound when I pressed the power button. So it was receiving power.

The next day the hairdryer lost power, but now it's working again.

The next day, the stove in the kitchen only worked for 1 second at a time and, because of the power, switched off and on again every second.

Could this be related to the iMac or is it more likely due to the power supply in the house?

Thanks in advance!