The correct option is
<span>D) can be transformed to different voltages
In fact, transformers can be used in order to change the voltage of an alternating current. This feature is particularly useful, because it allows to transmit electricity through power lines using very high voltages, and this allows to reduce the power dissipated along the lines.
In fact, the power generated by a power station is the product between the current and the voltage:
</span>
<span>So the current is:
</span>
(1)
<span>
The power dissipated along the transmission line, instead, is given by
</span>
<span>and if we use (1) inside this, we find
</span>
<span>so we see that the higher the voltage, the lower the power dissipated along the transmission lines.
Then, transformers are also used at the end of the power lines, in order to convert these very high voltages into the standard voltage (e.g. 240 V) used by household appliances.</span>
Answer:
Magnitude = 26 m
Direction = eastward
Explanation:
Given that a football coach walks 24 meters eastward, then 12 meters westward, then 36 meters eastward, and finally 22 meters westward. What is the magnitude and direction of the displacement?
Let eastward be positive and westward be negative.
Magnitude = 24 - 12 + 36 - 22
Magnitude = 60 - 34
Magnitude = 26
Since the answer is positive, the direction will be eastward.
Therefore,
Magnitude = 26 m
Direction = eastward
Answer:
(C) HBr is an acid .......
Answer:
A. 16.67 m/s
Explanation:
Speed or velocity refers to the rate of change in distance over a change in time. That is;
Speed = Distance ÷ time
Where;
Speed is in metre/seconds
Distance is in metre
Time is in seconds.
In this question, Steve throws a football 50 meters in 3 seconds. The average speed can be calculated this:
S = D/t
Where; d = 50m, t = 3s
S = 50/3
S = 16.6666666
S = 16.67m/s