Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 10 Answered

A conductor has a length of 2 0 m and a radius of 3 0 mm If the resistance is R= 100Ω, calculatethe new resistance if the same material has: (a) length=6 0 m and r=6 0 mm (b) length=1 0m and r=1 0mm ... If the resistance is R=100Ω, calculate the new resistance if the same material has: ...  (a) length = 6.0m and r=6.0mm(b) length=1.0m and r= 1.0mm.
Asked by bcnandi | 12 May, 2019, 14:14: PM
answered-by-expert Expert Answer
Resistance is directly proportional to length l  of wire and inversely proportional to area.
Since area is prportional to square of radius r, Resistance is inversely proportional to square of radius r.
 
Hence we write resistance as K×l/r2 where K is constant.
 
Resistance R of wire of 6 m length and 6 mm radius :-  begin mathsize 12px style R over 100 equals fraction numerator begin display style K cross times bevelled 6 over 36 end style over denominator begin display style K cross times bevelled 2 over 9 end style end fraction space equals space 0.75 end style  or  R = 75 Ω
 
Resistance R of wire of 1 m length and 1 mm radius :-  begin mathsize 12px style R over 100 equals space fraction numerator begin display style K cross times bevelled 1 over 1 end style over denominator begin display style K cross times bevelled 2 over 9 end style end fraction space equals space 4.5 end style   or  R = 450 Ω
 
 
Answered by Thiyagarajan K | 12 May, 2019, 14:55: PM

Application Videos

Concept Videos

Multiple Choice Questions Practice Test
Answered Unanswered My Questions My Answers
CBSE 10 - Physics
virtual image
Asked by sambhoorai | 27 Jul, 2024, 14:20: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
what is cornea
Asked by ramkrushnaramkrushna1 | 07 Jul, 2024, 19:01: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
Amar watching the birds sitting on top of a tree, at that time an ant bite his hand, he turned his head down to see his hand . Which part of eye helps him to adjust to see the top of a tree and also see his hand very nearly almost at same time?
Asked by mailtoparvathyprajith | 01 Jul, 2024, 13:16: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
explain the law of reflection how does it define the relation between the incident ray and the reflected and normal to the surface of the reflection
Asked by gs6070260 | 15 Jun, 2024, 20:45: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
A concave mirror has a focal length of 15 cm. If an object is placed 20 cm away from the mirror, find the position and nature of the image formed ????
question image
Asked by rv5238428 | 15 Jun, 2024, 19:43: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
concave mirror forms an image of an object placed 30 cm from the mirror. The image is formed 10 cm in front of the mirror. Calculate the focal length of the mirror.
Asked by diljotsingh68641 | 08 Jun, 2024, 19:03: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
draw a ray diagram for showing convergence of a parallel beam of light by a concave mirror and mark the position of pole and the centre of curvature in it
Asked by jainvandan708 | 07 Jun, 2024, 12:06: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
what is reflected ray
Asked by kk7629948076 | 03 Jun, 2024, 23:17: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
what type of image produced by plane mirror
Asked by agankitgupta938 | 18 Apr, 2024, 16:29: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 10 - Physics
how is light made
Asked by infinityupgraded | 13 Apr, 2024, 08:17: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt
Are You a Teacher or a Parent Seeking Customised Tests? Click here
×