Considering the definitipn of current, voltage, power, and Ohm's law,
The flow of electricity through an object, such as a wire, is known as current (I). Its unit of measurement is amps (A). So current is a measure of the speed at which the load passes through a given reference point in a specified direction.
The conductive force (electrical pressure) behind the flow of a current is known as voltage and is measured in volts (V) (voltage can also be referred to as the potential difference or electromotive force). That is, voltage is a measure of the work required to move a charge from one point to another.
Resistance (R) refers to the resistance or opposition that an element has to the passage of electric current. It is represented by the symbol Ω and indicates the resistance that an element offers to the passage of electricity.
This means that the greater the resistance to the passage of current, the lower the intensity or amount of electricity that passes through this conductor.
The resistance that is measured in ohms.
Ohm's law indicates that the current through a circuit is directly proportional to its voltage or voltage and inversely proportional to the resistance it presents.
Mathematically, Watt's law is expressed:
So if you want to find resistance, the expression for its calculation is:
In this case, you know:
Replacing:
Solving:
<u><em>R= 12.8 ohms</em></u>
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Habiba is right. The resistance is 12.8 ohms.
Learn more:
Answer:
(a) The self inductance, L = 21.95 mH
(b) The energy stored, E = 4.84 J
(c) the time, t = 0.154 s
Explanation:
(a) Self inductance is calculated as;
where;
N is the number of turns = 1000 loops
μ is the permeability of free space = 4π x 10⁻⁷ H/m
l is the length of the inductor, = 45 cm = 0.45 m
A is the area of the inductor (given diameter = 10 cm = 0.1 m)
(b) The energy stored in the inductor when 21 A current ;
(c) time it can be turned off if the induced emf cannot exceed 3.0 V;
Answer:
Explanation:
The heaviside function is defined as:
so we see that the Heaviside function "switches on" when, and remains switched on when
If we want our heaviside function to switch on when , we need the argument to the heaviside function to be 0 when
Thus we define a function f:
The term inside the heaviside function makes sure to displace the function 5 units to the right.
Now we just need to add a scale up factor of 240 V, because thats the voltage applied after the heaviside function switches on. ( when
, so it becomes just a 1, which we can safely ignore.)
Therefore our final result is:
I have made a sketch for you, and added it as attachment.
