5 Technological Devices for Alternating, Direct, and Human Energies????

Question

5 Technological Devices for Alternating, Direct, and Human Energies?

Don't ask me, I can't specify anymore. This is off of a study sheet and it'd be real helpful if someone could at least point me in the right direction. Thanks so much!

Answer 1

I guess you could classify a transformer or an AC generator as a device for "alternating energy"

And a battery as one for "direct energy"

And a bicycle or treadmill as one for "human energy"

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