As long as the batteries are putting out the exact same voltage, then yes you can use a battery with a higher ma rating.
Yes, you can use a 500mA (0.5A) supply instead of a 1A supply, but it depends on the requirements of your device. If the device draws more than 500mA, it may not function properly or could be damaged due to insufficient current. Always ensure that the power supply can meet the current demands of your application for safe and effective operation.
Nope.
No, it is not safe to touch battery terminals as they can deliver a harmful electric shock.
No, it is not safe to touch battery terminals with your hand as it can result in electric shock or burns.
No, it is not safe to touch car battery terminals as they can deliver a powerful electrical shock.
No, it is not safe to touch the negative battery terminal as it can cause electric shock or injury.
Yes. As long as the voltage is the same which it is. The 800mA is the capacity that the transformer can produce safely without going into an overload state. Your original adapter was rated at 500mA which means that what ever device was plugged into it draws less that 500mA. You might notice that the new adapter is slightly physically larger. So you are safe to use the new adapter with the higher rating.
no
Yes it will give you longer use time between charges.
Yes, it's safe I ordered a PSP battery from there
no
no