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Apple Introduces New 5W Charger With Folding Pins in United Kingdom

CausticSoda said:
No - schoolboy Physics 101. If you have half the voltage, the same appliance will use twice the current (amps) and it is current that does the damage. Ever had a static shock after walking on carpet, for example? That was many thousands of volts, but did you no damage, because the current is virtually nil. As another example, even though it is only 12 V, a car battery can do some damage because it is capable of delivering a very high current.
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As someone who has advanced well-beyond schoolboy physics and actually understands electricity, I suggest you research Ohms-law and the relationship of voltage and current with a fixed given resistance. Short version fixed resistance and double voltage means doubles current. So yes, voltage matters - a lot.
 
BurgDog said:
As someone who has advanced well-beyond schoolboy physics and actually understands electricity, I suggest you research Ohms-law and the relationship of voltage and current with a fixed given resistance. Short version fixed resistance and double voltage means doubles current. So yes, voltage matters - a lot.
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You're both right. He was not referring to a fixed resistance. He was referring to an appliance that draws a fixed amount of power. P = I * V.
 
chabig said:
You're both right. He was not referring to a fixed resistance. He was referring to an appliance that draws a fixed amount of power. P = I * V.
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The fixed resistance is the path through the human body and the current required to electrocute may be reached with higher voltages. 110 is less dangerous to people than 220. My point was that the UK connection system is over engineered for 110.
 
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BurgDog said:
As someone who has advanced well-beyond schoolboy physics and actually understands electricity, I suggest you research Ohms-law and the relationship of voltage and current with a fixed given resistance. Short version fixed resistance and double voltage means doubles current. So yes, voltage matters - a lot.
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Well both of you guys are saying, basically, the same thing.

In the case of a wall charger, the US version draws practically twice the AC INPUT current than the UK/EU versions will draw. Because the US AC voltage is about one half of the European AC voltage. Once the AC is converted to DC and stabilised (regulated) then you get 5V DC (1.0A, 2.1A, 2.4A or even higher; according to the design...) as the output.

But what is more noteworthy: A high DC Voltage (say a voltage over 100 volts DC) is more lethal for humans (as well as animals) compared to the same level of AC Voltage.
 
You'd think for an additional £10 they'd also put a type C port, to, you know, make it future-proof. Also - iPhone 7 and Watch are still shipping with the "old" USB cable only? Could have been handy and still fairly cheap to drop in a type C cable. Not sure they really want this type C thing to really take off after all.
 
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