CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

A uniform wire of resistance  20$$\Omega$$ having resistance  1$$\Omega / m$$  is bent in the form of circle as shown in fig. If the equivalent resistance between M and N is  1.8 $$\Omega$$ , then the length of the shorter section is :

11570.JPG


A
2 m
loader
B
5 m
loader
C
1.8 m
loader
D
18 m
loader

Solution

The correct option is A 2 m
$$ R = 20 \Omega$$
$$ L = 20 m$$
Let the length of the shorter section be x
length of longer section is (20-x)
$$ R_{eq} = \frac{x(20-x)}{20} = 1.8$$
   $$ 20x-x^{2} = 36$$
   $$ x^{2} - 20x + 36 = 0$$
   $$(x-2)(x-18) = 0$$
   $$ x= 2m$$
length of shorter side$$ = 2m$$

Physics

Suggest Corrections
thumbs-up
 
0


similar_icon
Similar questions
View More


similar_icon
People also searched for
View More



footer-image