1
JEE Advanced 2017 Paper 1 Offline
MCQ (More than One Correct Answer)
+4
-2
A human body has a surface area of approximately $$1\,m{}^2.$$ The normal body temperature is $$10$$ $$K$$ above the surrounding room temperature $${T_0}.$$ Take the room temperature to be $${T_0} = 300K.$$ For $${T_0} = 300\,K,$$ the value of $$\sigma T_0^4 = 460\,W{m^{ - 2}}$$ (where $$\sigma$$ is the Stefan-Boltzmann constant).

Which of the following options is / are correct?
A
The amount of energy radiated by the body in $$1$$ second is close to $$60$$ joules
B
If the surrounding temperature reduces by a small amount $$\Delta {T_0} < < {T_0},$$ then to maintain the same body temperature the same (living) human being needs to radiate $$\Delta W = 4\sigma T_0^3\Delta {T_0}$$ more energy per unit time
C
Reducing the exposed surface area of the body (e.g. by curling up) allows human to maintain the same body temperature while reducing the energy lost by radiation
D
If the body temperature rises significantly then the peak in the spectrum of electromagnetic radiation emitted by the body would shift to longer wavelengths
2
JEE Advanced 2015 Paper 2 Offline
MCQ (More than One Correct Answer)
+4
-2
A spherical body of radius R consists of a fluid of constant density and is in equilibrium under its own gravity. If P(r) is the pressure at r (r < R), then the correct option(s) is(are)
A
$$P(r = 0) = 0$$
B
$${{P(r = 3R/4)} \over {P(r = 2R/3)}} = {{63} \over {80}}$$
C
$${{P(r = 3R/5)} \over {P(r = 2R/5)}} = {{16} \over {21}}$$
D
$${{P(r = R/2)} \over {P(r = R/3)}} = {{20} \over {27}}$$
3
JEE Advanced 2015 Paper 2 Offline
MCQ (More than One Correct Answer)
+4
-2
In plotting stress versus strain curves for two materials P and Q, a student by mistake puts strain on the y-axis and stress on the x-axis as shown in the figure. Then, the correct statements is/are
A
P has more tensile strength than Q
B
P is more ductile than Q
C
P is more brittle than Q
D
The Young's modulus of P is more than that of Q
4
JEE Advanced 2015 Paper 2 Offline
MCQ (More than One Correct Answer)
+4
-2
Two spheres P and Q for equal radii have densities $$\rho$$1 and $$\rho$$2, respectively. The spheres are connected by a massless string and placed in liquids L1 and L2 of densities $$\sigma$$1 and $$\sigma$$2 and viscosities $${\eta _1}$$ and $${\eta _2}$$, respectively. They float in equilibrium with the sphere P in L1 and sphere Q in L2 and the string being taut (see figure) If sphere P along in L2 has terminal velocity vP and Q alone in L1 ha terminal velocity vQ, then

A
$${{|{v_P}|} \over {|{v_Q}|}} = {{{\eta _1}} \over {{\eta _2}}}$$
B
$${{|{v_P}|} \over {|{v_Q}|}} = {{{\eta _2}} \over {{\eta _1}}}$$
C
vP . vQ > 0
D
vP . vQ < 0
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