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:
The correct option is A. 18 V
Therefore,
Explanation:
Given:
Total Voltage,
V = 56 V,
Voltage drop


To Find:
(Assumed ,as it is not given clearly in the question)
Solution:
So in series combination total Voltage is given as

Substituting the values we get

Therefore,
To solve this problem we will apply the concepts related to the conservation of momentum. The momentum can be defined as the product between the mass of the object and its velocity, and the conservation of the momentum as the equality between the change of the initial momentum versus the final momentum. Mathematically, this relationship can be described as

Here,
= Mass of each object
= Initial velocity of each object
= Final velocity of each object
According to the statement one of the bodies does not have initial velocity, therefore said term would be zero. And the equation could be rewritten as,

Replacing the values respectively (The mass of your body with its respective speed we would have)



Therefore the initial velocity of the 2kg cart is 0.55m/s