Answer:
<h2>
d₂ = 3d</h2><h2>
The diameter of the second wire is 3 times that of the initial wire.</h2>
Explanation:
Using the formula for calculating the resistivity of an object to find the diameter.
Resistivity P = RA/L
R is the resistance of the material
A is the cross sectional area
L is the length of the material
Since A = πd²/4
P = R( πd²/4)/L
P = Rπd²/4L ... 1
If the second wire of the same material and length is found to have resistance R/9, the resistivity of the second material will be;
P₂ = (R/9)A₂/L₂
P₂ = (R/9)(πd₂²/4)/L₂
P₂ = (Rπd₂²/36)/L₂
P₂ = (Rπd₂²)/36L₂
Since the length and resistivity are the same;
P = P₂ and L =L₂
Equating 1 and 2;
Rπd²/4L = (Rπd₂²)/36L₂
Rπd²/4L = (Rπd₂²)/36L
d² = d₂²/9
d₂² = 9d²
Taking the square root of both sides;
√d₂² = √9d²
d₂ = 3d
Therefore the diameter of the second wire is 3 times that of the initial wire
Answer:
Work done to pull the piano upwards is 401250 J
Explanation:
Work is done against the gravity to pull the piano upwards
So here we can say that work done is

here we know that

also we know that
H = 75 m
now we have


Answer:
Two stars, each of mass M, form a binary system. ... used is the distance between the centers of the planets; here that distance is 2R. ... r appears in the denominator of Newton's law of gravitation, the force of ... The orbital speed of a satellite orbiting the earth in a circular orbit at the ... is undergoing uniform circular motion?
Explanation:
Two stars, each of mass M, form a binary system. ... used is the distance between the centers of the planets; here that distance is 2R. ... r appears in the denominator of Newton's law of gravitation, the force of ... The orbital speed of a satellite orbiting the earth in a circular orbit at the ... is undergoing uniform circular motion?
Answer:
220 V
Explanation:

As the resistors are connected in series,

= 20 + 30 + 60
= 110 ohms
V = IR
= 2 * 110
= 220 V
Hope it helps