the circumference is C = 2pi*r. Make sure your answer is in meters, not cm.
Opposite ends of the diameter are half that far apart.
Now just multiply that by 12.
A wire of resistance 12 ohm per metre is bent to form a complete circle of radius 10 c.m.the resistance between its two diametrically opposite point A and B
3 answers
R across A-B= R/2=(1/2)pie r rho=1/2(pie*10*0.1*12 = 0.6pie ohms.
Total resistance of wire = 12Ω×2π×10
−1
= 2.4π
Resistance of each half =
2
2.4π
=1.2π
and as about diameter both parts are in parallel
Req. =
2
1.2π
=0.6πΩ
−1
= 2.4π
Resistance of each half =
2
2.4π
=1.2π
and as about diameter both parts are in parallel
Req. =
2
1.2π
=0.6πΩ