Answer:
R' = R/2
Therefore, the new resistance of the wire is twice the value of the initial resistance.
Explanation:
Consider a wire with:
Resistance = R
Length = L
Area = A = πr²
where, r = radius
ρ = resistivity
Then:
R = ρL/A
R = ρL/πr² --------------- equation 1
Now, the new wire has:
Resistance = R'
Resistivity = ρ
Length = L' = 2 L
Radius = r' = 2r
Area = πr'² = π(2r)² = 4πr²
Therefore,
R' = ρL'/πr'²
R' = ρ(2 L)/4πr²
R' = (1/2)(ρL/πr²)
using equation 1:
<u>R' = R/2</u>
<u>Therefore, the new resistance of the wire is twice the value of the initial resistance.</u>
Answer:
2 0.00130719 m/s
Explanation:
Now we have
7.86 furlongs/fortnight
7.86 x 220 yards / fortnight
1729.2yards / fortnight
1647.8 yards / 14 days
123.5yards / day
So
123.5 x 0.9144 meter / day
112.meters / day
=112.9meters / 86400s
= 0.001307m/s
Magnets attract or repel other magnets.
No.A hypothesis is an educated guess but it will not always be right
