Answer:
r₁/r₂ = 1/2 = 0.5
Explanation:
The resistance of a wire is given by the following formula:
R = ρL/A
where,
R = Resistance of wire
ρ = resistivity of the material of wire
L = Length of wire
A = Cross-sectional area of wire = πr²
r = radius of wire
Therefore,
R = ρL/πr²
<u>FOR WIRE A</u>:
R₁ = ρ₁L₁/πr₁² -------- equation 1
<u>FOR WIRE B</u>:
R₂ = ρ₂L₂/πr₂² -------- equation 2
It is given that resistance of wire A is four times greater than the resistance of wire B.
R₁ = 4 R₂
using values from equation 1 and equation 2:
ρ₁L₁/πr₁² = 4ρ₂L₂/πr₂²
since, the material and length of both wires are same.
ρ₁ = ρ₂ = ρ
L₁ = L₂ = L
Therefore,
ρL/πr₁² = 4ρL/πr₂²
1/r₁² = 4/r₂²
r₁²/r₂² = 1/4
taking square root on both sides:
<u>r₁/r₂ = 1/2 = 0.5</u>
Answer
Explanation:
As the three resistors are connected in series, the expression to be used for the
calculation of RT equivalent resistance
is:
RT = R1 + R2 + R3
We replace the data of the statement in the previous expression and it remains:
5 10 15 RT + R1 + R2 + R3 + +
We perform the mathematical operations that lead us to the result we are looking for:
RT - 30Ω
The voltage in the extension cord is 30 V.
The problem above can be solved using ohm's law
⇒ Formula:
V = IR.................. Equation 1
⇒ Where:
- V = Voltage in the extension cord
- I = Current flowing through the extension cord
- R = Resistance of the extension cord.
From the question, I think there was a slight error in the value of the current given it suppose to be 500 A, and not 5.00 A
⇒ Given:
⇒ Substitute these values into equation 1
Hence the voltage in the extension cord is 30 V
Learn more about voltage here: brainly.com/question/4429782
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Answer:
The pressure exerted by the woman on the floor is 1.9061 x 10⁷ N/m²
Explanation:
Given;
mass of the woman, m = 55 kg
diameter of the circular heel, d = 6.0 mm
radius of the heel, r = 3.0 mm = 0.003 m
Cross-sectional area of the heel is given by;
A = πr²
A = π(0.003)²
A = 2.8278 x 10⁻⁵ m²
The weight of the woman is given by;
W = mg
W = 55 x 9.8
W = 539 N
The pressure exerted by the woman on the floor is given by;
P = F / A
P = W / A
P = 539 / (2.8278 x 10⁻⁵ )
P = 1.9061 x 10⁷ N/m²
Therefore, the pressure exerted by the woman on the floor is 1.9061 x 10⁷ N/m²