Which statement is NOT true about voltage?

A higher voltage means a faster current.

All electricity sources have the same voltage.

Voltage is the difference in electrical potential energy.

The unit for voltage is volt (v).

The first two choices are both false, but the second one is the falser one.

All electricity sources do not have the same voltage. The outlet in your bedroom wall supplies 120 volts, but the USB port on your laptop only supplies 5 volts, and the battery in your cellphone only supplies 3.7 volts.