Thermal Properties of Matter-Quiz-17

 

THERMAL PROPERTIES OF MATTER QUIZ-17

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.

Q161. A wire of length L_0 is supplied heat to raise its temperature by T. If γ is the coefficient of volume expension of the wire and Y is Young’s modulus of the wire then the energy density stored in the wire is

•  √1/2 γ² T² Y
•  √1/3 γ² T² Y³
•  1/18 (γ² T²)/Y
•  1/18 γ² T² Y

Solution

Q162. There are two thin spheres A and B of the same material and same thickness. They behave like black bodies. Radius of A is double that of B and both have same temperature T. When A and B are kept in a room of temperature T_0 (

•  2:1
•  1:1
•  4:1
•  8:1

Solution

Q163. A spherical black body with a radius of 12 cm radiates 440 W power at 500K. If the radius were halved and the temperature doubled, the power radiated in watt would be

•   225
•  450
•  900
•  1800t

Solution

Q164. Two identical calorimeters, each of water equivalent 100 g and volume 200 cm^3, are filled with water and a liquid. They are placed in identical constant-temperature enclosures to cool down. The temperatures are plotted at different times (the choice of units are completely arbitrary) as shown in Figure. If the density of the liquid is 800 kgm^(-3), then its specific heat capacity is

•  8400 J/kg°C
•  2100 J/kg°C
•  1312.5 J/kg°C
•  1680.5 J/kg°C

Solution

Q165. A thermally insulated piece of metal is heated under atmospheric pressure by an electric current so that it receives electric energy at a constant power P. This leads to an increase of absolute temperature T of the metal with time t as follows: T(t)=T_0 [1+a(t-t_0 )]^(1/4). Here,a,t_0 and T_0 are constants the heat capacity C_p (T) of the metal is

•  4P/(aT_0 )
•  (4PT³)/(aT_0⁴ )
•  (2PT³)/(aT_0⁴ )
•  2P/(aT_0 )

Solution
 

Q166. A calorimeter contains 0.2 kg of water at 30°C. 0.1 kg of water at 60°C is added to it, the mixture is well stirred and the resulting temperature is found to be 35°C. The thermal capacity of the calorimeter is

•  6300 J/K
•  1260 J/K
• 4200 J/K
•  None of these

Solution

10500=4200+5X⇒X=1260 J

Q167. A solid whose volume does not change with temperature floats in a liquid. For two different temperature t_1 and t_2 of the liquid, fractions f_1and f_2 of the volume of the solid remain submerged in the liquid. The coefficient of volume expansion of the liquid is equal to

•  (f_1-f_2)/(f_2 t_1-f_1 t_2 )
•  (f_1-f_2)/(f_1 t_1-f_2 t_2 )
•  (f_1+f_2)/(f_2 t_1-f_1 t_2 )
•  (f_1+f_2)/(f_1 t_1+f_2 t_2 )

Solution

Q168. A drilling machine of 10 kW power is used to drill a bore in a small aluminium block of mass 8 kg. If 50% of power is used up in heating the machine itself or lost to the surroundings then how much is the rise in temperature of the block in 2.5 min (given: specific heat of aluminium=0.91 J/g°C)?

•  103°C
•  130°C
•  105°C
•  30°C

Solution

Q169. An ideal gas is expanding such that PT^2= constant. The coefficient of volume expansion of the gas is

•  1/T
•  2/T
•  3/T
•  >4/T

Solution

Q170. A uniform metal rod is used as a bar pendulum. If the room temperature rises by 10°C, and the coefficient of linear expansion of the metal of the rod is 2×10^(-6) per °C, the period of the pendulum will have percentage increases of

•  -2×10^(-3)
•  -1×10^(-3)
•  2×10^(-3)
• 1×10^(-3)

Solution