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Okay. Resistance by ohms law is given by R = V/I
But Power P = V * I
Dividing R/P = 1/ I 2
Or R = P / I squared
For a constant power, resistance is inversely proportional to I squared and not simply proportional to.
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What does resistance in wire depend on?
Resistance is directly proportional to the resistivity and length of the conductor, and inversely-proportional to its cross-sectional area. As resistivity is affected by temperature, we can say that temperature indirectly affects resistance.
Wires 1 and 2 are made of the same metal. Wire 2 has twice the length and twice the diameter of wire 1. What is the ratio of the resistances of the two wires?
Wire 1 has radius R, and wire 2 has radius 2R. Wire 1 has length L and wire 2 has length 2L. Since resistance is inversely proportional to cross sectional area and proportional to length resistance of wire 1 is:c*L/pi*R^2, where c is a constant based on the material.The resistance of wire 2 is:c * 2L/pi *(2R)^2, or squaring the 2R term we have c * 2L/pi * 4R^2, and simplifying we have: c*L/2pi*R^2.Now, to get the ratio of wire 1 to wire 2 we divide equation 1 by equation 2 and simplify:c*L/pi*R^2 / c*L/2pi * R^2. When you divide a fraction by another fraction you invert and multiply, so this becomesc*L *2piR^2 / c*L *pi * R^2. Each of the variables cancel leaving the ratio of resistance of wire 1 to wire 2 is 2:1, or wire 1 has twice the resistance of wire 2 even though wire 2 is twice as long.An Alternative AnswerResistance is directly proportional to length, and inversely proportional to cross sectional area. The cross-sectional area of a circle is proportional to the square of the diameter. So, conductor 2 is twice as long, so you can double its resistance; but its diameter is doubled, so its resistance is then reduced by a quarter. So the resistance of conductor 2 is half that of conductor 1!
What is the formula of relation between resistance and area of a wire?
If the area you're referring to is the cross-sectional area of the conductor: you can think of the cross-sectional area of a wire as the thickness of that wire. If you bundled two wires together in parallel, that would be a bit like having one, thicker wire, wouldn't it? So increasing the area is analogous to adding more pathways for current to travel in parallel. Metals carry current on their surface, but also through electron "bands" in their interior -- increasing area means adding more bands = adding more pathways. And adding more pathways reduces resistance.
Maximum moment of resistance of beam?
Rm= 8Mp/L
What would result from increasing the resistance in a series circuit with one resistance (load)?
Resistance refers to the property of a substance that impedes the flow of electric current. Some substances resist current flow more than others. If a substance offers very high resistance to current flow it is called an insulator. If its resistance to current flow is very low, it is called a conductor. Resistivity refers to the ability of substances to resist current flow. Good conductors have low resistivity and insulators have high resistivity.Factors upon which resistance dependsThe resistance R of a conductori. is directly proportional to its lengthii. is inversely proportional to its area of X-sectioniii. nature of the materialiv. changes with temperature.From the first three points, R = p l/ A where p = rho and is a constant of proportionalityOr, if the resistance is increased,current flow will decrease(I = V/R).Looking at the first three factors ,area of X-section will be decreasing.
What measure did they employ to lessen the resistance?
We can reduce the supply voltage from the ohms law relation.......v=ir... resistance is directly proportional to supply voltage...or.....we can control the resistance by the relation by R is directly proportional to l/a l=length a=area
How would resistance r depend on cross section and length of the material?
Resistance (R) of a material depends on both its cross-sectional area (A) and length (L) according to the formula R = ρ * L / A, where ρ is the material's resistivity. The resistance is directly proportional to the length of the material and inversely proportional to its cross-sectional area. This means that as the length of the material increases, the resistance also increases, while as the cross-sectional area increases, the resistance decreases.
How would resistance depend on cross section and length of the material?
Resistance R =p(L /A)i,e Resistance(R) of a conductor will be directly proportional to its length(L) ==> if the length of the conductor increases its resistance also will increase.i,e Resistance(R) of a conductor is inversely proportional to its cross section area(A) ==> if the Area of the conductor increases its resistance also will decrease.
What is the law of resistance?
The law of resistance states that the resistance in a circuit is directly proportional to the length of the conductor, and inversely proportional to its cross-sectional area and the material's resistivity. It can be calculated using the formula R = ρ * (L/A), where R is resistance, ρ is resistivity, L is length, and A is cross-sectional area.
What is the relationship between insulation resistance and length of conductor in transformers?
when length is increased insulation resistance of cable is decresed i.e.,R is inversely proportional to L where R is resistance L is length
How does thickness of a wire affect resistance?
Resistance is inversely proportional to cross-sectional area. so ,if the thickness of the wire increases, the area of cross-section increases and this results in decrease of the resistance. The resistance R = l p / A where R is the resistance, l is the length of the wire, p(rho) is the electrical resistivity of the material and A is the area of cross section. So R the resistance is inversely proportional to A the area of cross-section. If R increases
What would not reduce resistance in the copper wire?
Increasing the length of the wire will not reduce resistance in a copper wire. In fact, resistance is directly proportional to the length of the wire according to the formula R = ρ * (L/A), where R is resistance, ρ is resistivity, L is length, and A is cross-sectional area.
What does resistance in wire depend on?
Resistance is directly proportional to the resistivity and length of the conductor, and inversely-proportional to its cross-sectional area. As resistivity is affected by temperature, we can say that temperature indirectly affects resistance.
How do you find length and crosssectional area of a wire given just resistancevolume and resistivity?
Resistance varies directly as length Resistance varies inversely as cross-sectional area Hence R varies as L and R varies as 1/A Thus R = r(L/A) where r is the coefficient of resistance of the wire. If the wire is of uniform cross section, then A = V/L where V is the volume of the wire. Hence now we have R = r(L/(V/L)) or R = r(L-squared/V) or L-squared = (RxV)/r and so the answer would be L = square-root of (RxV)/r
How does the resistance of a wire vary with its length?
The resistance of a wire is directly proportional to its length. This means that as the length of the wire increases, the resistance also increases. This relationship is described by the formula R = ρ * (L/A), where R is resistance, ρ is the resistivity of the material, L is the length of the wire, and A is its cross-sectional area.
What will happen to the resistance of a wire if it is stretched to increase its length by 2 times?
If a wire is stretched to increase its length, its resistance will also increase. Resistance is directly proportional to the length of the wire, so doubling the length will double the resistance, assuming the wire remains the same thickness and material.
How does an object length affect its electrical resistance?
As the length of an object increases, its electrical resistance also increases. This is because a longer object provides more path for the electrons to travel through, resulting in more collisions and a higher resistance to the flow of current. The relationship between length and resistance is directly proportional according to the formula R = ρ * (L/A), where R is resistance, ρ is resistivity, L is length, and A is cross-sectional area.
