In above the question please give the answer of question - 8,11:

8. resistance R is stretched uniformly to a wire of radius r/2. The new resistance is.
(A) 16 R         (B) 4 R       (C) R/4         (D) R/16
 

11. A resistor of 20 cm length and resistance 5 ohm is stretched to a uniform wire of 40 cm length. The resistance now is-

(A) 10 ohm              (B) 5 ohm

(C) 20 ohm               (D) 200 ohm