You can't derive watts from hertz. All devices plugged into the outlet in a certain region work with the same frequency (hertz).
A microwave oven might use somewhere around 1 kW. You can look at your specific device and search for a small metal plate which has the electrical specifications.
550 watts at max power.
1540 Watts
1200
Multiply the current by the voltage: 120 times 0.3, which is 40 watts.
700W, .7 cubic ft
You need amps
1500 watts
Depends on how many watts the microwave is.
550 watts at max power.
The microwave oven uses 1350 watts at 12 amps input and the microwave output is 800 watts.
1540 Watts
The Whirlpool MT4155SPQ 1.5 CuFt Countertop Microwave Oven supplies 1200 watts of power.
It has 1000 watts
1200
Multiply the current by the voltage: 120 times 0.3, which is 40 watts.
There are 1350 watts in a 60 hz bulb. There is a push not for everyone to transfer to led bulbs.
A typical microwave is 750-800 watts. There are lower (and higher) power machines, but the 'normal' for general use is 750-800 watts.