R is proportional to the length of the wire:
R ∝ length
R is also proportional to the inverse square of the diameter:
R ∝ 1/diameter²
The resistance of a wire 2700ft long with a diameter of 0.26in is 9850Ω. Now let's change the shape of the wire, adding and subtracting material as we go along, such that the wire is now 2800ft and has a diameter of 0.1in.
Calculate the scale factor due to the changed length:
k₁ = 2800/2700 = 1.037
Scale factor due to changed diameter:
k₂ = 1/(0.1/0.26)² = 6.76
Multiply the original resistance by these factors to get the new resistance:
R = R₀k₁k₂
R₀ = 9850Ω, k₁ = 1.037, k₂ = 6.76
R = 9850(1.037)(6.76)
R = 69049.682Ω
Round to the nearest hundredth:
R = 69049.68Ω
Yes that's a true statement. That's why grandmother put a hot water bottle to warm up her bed, and not a hot bar of steel or lead.
Answer:
-10.8m/s^2
Explanation:
a=change in velocity/change in time
-27 m/s/2.5=10.8m/s^2
or if its not negative
27m/s/2.5=10.8m/s^2
Based on this, you can tell that Iron(Fe) does not react with Nitrogen(N), but does with something in normal air. The element the Iron is reacting with Oxygen(O), and the compound that is formed is called iron oxide.
<span>When two waves of same frequency travel in a medium simultaneously in the same direction then, due to their superposition, the resultant intensity at any point of the medium is different from the sum of intensities of the two waves. At certain points the intensity of the resultant wave has a large value while at some points it has a very small or zero. This is called wave interference.</span>
