Thermal Properties of Matter-Quiz-13

 

THERMAL PROPERTIES OF MATTER QUIZ-13

Dear Readers,

JEE Advanced Physics Syllabus can be referred by the IIT aspirants to get a detailed list of all topics that are important in cracking the entrance examination. JEE Advanced syllabus for Physics has been designed in such a way that it offers very practical and application-based learning to further make it easier for students to understand every concept or topic by correlating it with day-to-day experiences. In comparison to the other two subjects, the syllabus of JEE Advanced for physics is developed in such a way so as to test the deep understanding and application of concepts.

Q121. The apparent coefficient of expansion of a liquid when heated, filled in vessel A and B of identical volumes, is found to be γ_1 and γ_2, respectively. If α_1 be the linear expansivity of A then that of B will be

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Solution

Q122. A planet is at an average distance d from the sun and its average surface temperature is T. Assume that the planet receives energy only from the sun and loses energy only through radiation from the surface. Neglect atmospheric effects. If T∝d^(-n), the value of n is

•  2
•  1
•  1/2
•  1/4

Solution

Q123. A point source of heat of power P is placed at the centre of a spherical shell of mean radius R. The material of the shall has thermal conductivity K. If the temperature difference between the outer and the inner surface of the shell is not to exceed T, then the thickness of the shell should not be less than

•   (2πR² KT)/P
•  (4πR>² KT)/P
•  (πR² KT)/P
•  (πR² KT)/4P

Solution

Q124. A body cools in 7 min from 60°C to 40°C. What will be its temperature after the next 7 min? The temperature of surroundings is 10°C

•  28°C
•  25°C
•  30°C
•  22°C

Solution

Q125. The specific heat of a substance varies with temperature t(°C) as c=0.20+0.14t+0.023t² (cal/g/℃) The heat required to raise the temperature of 2 g of substance from 5℃ to 15℃ will be

•  24 cal
•  56 cal
•  82 cal
•  100 c

Solution
 

Q126. A slab consists of two parallel layers of copper and brass of the same thickness and having thermal conductivities in the ratio 1:4. If the free face of brass is at 100℃ and that of copper at 0℃, the temperature of interface is

•  80℃
•  20℃
• 60℃
•  40℃

Solution

Q127. A lead bullet at 27℃ just melts when stopped by an obstacle. Assuming that 25% of heat is absorbed by the obstacle, then the velocity of the bullet at the time of striking (M.P. of lead =327℃, specific heat of lead =0.03cal/g℃, latent heat of fusion of lead =6cal/g and J=4.2joule/cal)

•  410m/s
•  1230m/s
•  307.5m/s
•  None of the above

Solution

Q128. The radiation emitted by a star A is 1000 times that of the sun. If the surface temperatures of the sun and star A are 6000 K and 2000 K, respectively, the ratio of the radii of the star A and the sun is

•  300:1
•  600:1
•  900:1
•  1200:1

Solution

Q129. Two rods (one semi-circular and other straight) of same material and of same cross-sectional area are joined as shown in figure. The points A and B are maintained at different temperatures. The ratio of the heat transferred through a cross section of a semi-circular rod to the heat transferred through a cross section of the straight rod in a given time is

•  2:π
•  1:2
•  π:2
•  >3:2

Solution

Q130. The coefficient of linear expansion of glass is α_s per °C and the cubical expansion of mercury is γ_m per °C. The volume of the bulb of a mercury thermometer at 0°C is V_0 and cross section of the capillary is A_0. What is the length of mercury column in capillary at T°C, if the mercury just fills the bulb at 0°C?

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Solution