Properties of Solids & Fluids · JEE Main previous year questions

2017 2 questions

1. Q332017 · 9 Apr 2017 · Shift 1

   A steel rail of length 5 m and area of cross section $40{\mathrm{cm}}^2$ is prevented from expanding along its length while the temperature rises by $10^{\circ }\mathrm{C}$. If coefficient of linear expansion and Young’s modulus of steel are $1.2\times 10^{-5}{\mathrm{K}}^{-1}$ and $2\times 10^{11}\mathrm{N}{\mathrm{m}}^{-2}$ respectively, the force developed in the rail is approximately :

   1. A.$2\times 10^7\mathrm{N}$
   2. B.$1\times 10^5\mathrm{N}$
   3. C.$2\times 10^9\mathrm{N}$
   4. D.$3\times 10^{-5}\mathrm{N}$
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   Answer: B

2. Q342017 · 9 Apr 2017 · Shift 1

   Two tubes of radii $r_1$ and $r_2$, and lengths $l_1$ and $l_2$ , respectively, are connected in series and a liquid flows through each of them in stream line conditions. ${\mathrm{P}}_1$ and ${\mathrm{P}}_2$ are pressure differences across the two tubes. If ${\mathrm{P}}_2$ is $4{\mathrm{P}}_1$ and $l_2$ is $\frac{l_1}{4}$ , then the radius $r_2$ will be equal to :

   1. A.$r_1$
   2. B.$2r_1$
   3. C.$4r_1$
   4. D.$\frac{r_1}{2}$
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   Answer: D