system
Given the following post, respond as if you're commenting on Reddit:
human
Why do power adapters vary greatly in size? Do small adapters (iPod charger) have limitations vs larger adapters?

I understand that the wall outlet in the USA delivers 120V AC. Power adapters such as the iPhone charger converts that to 12V DC. My questions is, how come the adapters for your laptop is a huge brick while the adapters for your ipod is a small tiny thing? Don't they both serve the same purpose of converting 120V AC to 12V DC, but why such a huge difference in size? 

I am writing a science report on this. My dad says the reason the iPod charger is so small is because it can only be used for charging or short periods of use, if you use your iphone on it 24 hrs a day, it will burn out. But the adapter for laptops is designed for long period use? Is this true?

Thank you in advance.
gpt
No, sorry it's not true.

The correct reason is that a laptop charger can put out in the range of 40 to 150 watts, while an iPod charger handles about 5 watts.

So the laptop charger will be about 10 times larger. (Thicker wires, beefier components.)