Taking the resistivity of platinoid as 3.3 x 10-7 m, find the resistance of 7.0 m of platinoid wire of average diameter 0.14 cm.
1.50
resistance = (resistivity * length)/area
so, just plug in your numbers...
watch the units.
1.50ohm
To find the resistance of the platinoid wire, we can use the formula:
Resistance (R) = resistivity (ρ) x length (L) / cross-sectional area (A)
First, let's calculate the cross-sectional area of the platinoid wire:
Given:
Diameter (d) = 0.14 cm
We can use the formula for the area of a circle:
Area (A) = π x (diameter/2)^2
Plugging in the values, we get:
A = π x (0.14 cm / 2)^2
Next, let's convert the diameter and length into meters:
Diameter (d) = 0.14 cm = 0.14 cm / 100 cm/m = 0.0014 m
Length (L) = 7.0 m
Now we can substitute the values into the formula for resistance:
R = ρ x L / A
R = (3.3 x 10^(-7) m) x (7.0 m) / [π x (0.0014 m / 2)^2]
Calculating this expression will give us the resistance of the platinoid wire.