JEE PYQ: Properties Of Matter Question 2
Question 2 - 2021 (18 Mar 2021 Shift 1)
Two separate wires A and B are stretched by 2 mm and 4 mm respectively, when they are subjected to a force of 2 N. Assume that both the wires are made up of same material and the radius of wire B is 4 times that of the radius of wire A. The length of the wires $A$ and $B$ are in the ratio $a : b$. Then $a/b$ can be expressed as $1/x$ where $x$ is ____
Show Answer
Answer: 32
Solution
For A: $\frac{E}{\pi r^2} = y \frac{2\text{ mm}}{a}$ …(1)
For B: $\frac{E}{\pi (4r)^2} = y \frac{4\text{ mm}}{b}$ …(2)
(1)/(2): $16 = \frac{2b}{4a}$, so $\frac{a}{b} = \frac{1}{32}$. Answer $= 32$
BETA
