Consider a cube of material of sides 1 cm with a resistance of 0.003 Ω between its opposite
faces. What is the resistance if the same volume of the material is drawn into a length of 50
cm with a uniform cross – section?
A) 0.003 Ω B) 0.15 Ω
C) 7.5 Ω D) None of these

• R = pl/A
  0.003 = p*1 cm/(V)
  0.003= p/(V)..............(1)
  For 50 cm cube,for same volume of the material divide volume(v) by 50
  R’ = p*50/(v/50)
  R’ = p*2500/(v)....................(2)
  solving (1) and (2)
  we get R'=7.5 ohm
• 8 years agoHelpfull: Yes(3) No(0)