The answer is The ability to carry power across long distances. The movement of electrical current is constantly reversing direction.AC current reverses direction 60 times per second. It is very easy to adjust the voltage of AC using a device known as a transformer. P<span>ower companies can transmit power at extremely high voltage levels and then transform the voltage down to 120 volts inside the house.</span> The ability to carry power across long distances was the most important advantage of AC over DC.
The box stopped moving because there was a negative acceleration in the x direction caused by friction. To find the average speed, simply divide the displacement by time: 10 / 2 = 5 m/s
The formula for frequency is f = 1/T where f is frequency and T is period in seconds. You have you period which is 0.008s and that is all you will need to solve or frequency in a wave: f = 1/2 f = 1/0.008s f = 125Hz
