# Need help some physics problems?

How would I solve problems when given this:

Let RS = R. If R1 = 50 Ω and R2 = 25 Ω and I = 0.15 A, find V.

Let RP = R. If R1 = 50 Ω and R2 = 25 Ω and I = 0.15 A, find V.

Given R = 110 Ω, l = 1.0 m, and A = 22×10-6 m2 , find ρ.

Relevance

I would guess that "RS" is telling is that the resistors are in series, and the "RP" means that they are in parallel.

If that's correct, then

a/ Rs = 75 Ω, and so

voltage V = I*R = 0.15A * 75Ω = 11 V

b/ Rp = 1 / (1/50 + 1/25) Ω = 17 Ω

and so

V = 0.15A * 17Ω = 2.5 V

c/ R = ρL/A

so

ρ = RA/L = 110Ω * 22e-6m² / 1.0m = 0.00242 Ω·m

Hope this helps!

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• Need a diagram or figure !

• Mario6 months agoReport

Im not given any diagram but rather given equations: R = pl/a
Rs= (R1 + R2 + R3 + ... + Ri) = ΣRi
1/Rp = 1/R1 + 1/R2 + 1/R3 + ... + 1/Ri) = ∑i 1/Ri

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• you need a drawing to show where all these resistors are located with respect to each other.

• billrussell42
Lv 7
6 months agoReport

The first one appears to be:
Resistance of a wire in Ω
R = ρL/A
ρ is resistivity of the material in Ω-m
L is length in meters
A is cross-sectional area in m²
A = πr², r is radius of wire in m

again, equations are meaningless unless the symbols are defined.

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