Please wait...
Contact Us
Contact
Need assistance? Contact us on below numbers

For Study plan details

10:00 AM to 7:00 PM IST all days.

For Franchisee Enquiry

OR

or

Thanks, You will receive a call shortly.
Customer Support

You are very important to us

For any content/service related issues please contact on this number

93219 24448 / 99871 78554

Mon to Sat - 10 AM to 7 PM

17 question

qsnImg
Asked by saharanmanish44 3rd October 2023, 7:43 PM
Answered by Expert
Answer:
Resistance R = ρ × ( L / A ) , where ρ is resistivity , L is length of wire and A is area of cross section of wire.
 
If resistance of given wire is 1 Ω , then begin mathsize 14px style R space equals space rho space cross times L over A end style = 1 Ω
If wire is stretched so that length L is increased to 1.25 L , then cross section area  becomes ( A/1.25)  because volume of wire is constant .
 
If length increases then area decreases by same proportion .
 
New resistance R' is
 
begin mathsize 14px style R apostrophe space equals space rho space cross times space fraction numerator L apostrophe over denominator A apostrophe end fraction end style = begin mathsize 14px style rho space cross times space fraction numerator 1.25 space L over denominator left parenthesis space A space divided by space 1.25 right parenthesis end fraction space equals space left parenthesis 1.25 right parenthesis squared space rho space cross times L over A space equals space 1.5625 space R end style
Increase in resistance is 56 %
Answered by Expert 4th October 2023, 8:01 AM
Rate this answer
  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10

You have rated this answer /10

Your answer has been posted successfully!

Chat with us on WhatsApp