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Wire A X is fold back at p such that /AP/= 40cm and its parallel with px which is 60cm long to form parallel combination. Calculate the effective resistance of the parallel combination if the resistance per unit length of the material of tge wire

User David Eyk
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Answer: To find the total resistance of the wires, we need to use a formula that takes into account the length and cross-sectional area of the wires and the resistivity of the material they are made of. By plugging in the appropriate values for the length, cross-sectional area, and resistivity of the wires in the formula, we can find the individual resistances of the wires. Then, by using another formula for the total resistance of a parallel combination, we can find the effective resistance of the wires in parallel.

Step-by-step explanation:R = ρ * (L / A)

where R is the resistance of the wire, ρ is the material's resistivity (resistance per unit length), L is the length of the wire, and A is the cross-sectional area of the wire.
according to the given data
AP= 40 cm
px=60cm

Next, we need to calculate the wire PX's length and cross-sectional area. The length is given as 60 cm, and we can assume the same diameter of 1 mm, giving a cross-sectional area of 0.785 mm^2.

Now we can calculate the resistance of each wire using the formula above:

R_AX = ρ * (80 cm / 0.785 mm^2) = 101.91 * ρ

R_PX = ρ * (60 cm / 0.785 mm^2) = 76.43 * ρ

The total resistance of the parallel combination is given by the formula:

1/R_total = 1/R_AX + 1/R_PX

Substituting the values of R_AX and R_PX, we get:

1/R_total = 1/(101.91 * ρ) + 1/(76.43 * ρ)

1/R_total = (1.55 / ρ)

R_total = ρ / 1.55

therefore, the effective resistance of the parallel combination is (ρ / 1.55) ohms

User Aryan Bahmani
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