Thermal Properties of Matter-Quiz-14

 

THERMAL PROPERTIES OF MATTER QUIZ-14

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.

Q131. A room at 20°C is heated by a heater of resistance 20 ohm connected to 200 V mains. The temperature is uniform throughout the room and the heat is transmitted through a glass window of area 1 m² and thickness 0.2 cm. Calculate the temperature outside. Thermal conductivity of glass is 0.2 cal/m C° s and mechanical equivalent of heat is 4.2 J/cal

•  13.69°C
•  15.24°C
•  17.85°C
•  19.96°C

Solution

Q132. Two spherical bodies A (radius 6 cm) and B (radius 18 cm) are at temperature T_1 and T_2 respectively. The maximum intensity in the emission spectrum of A is at 500 nm and in that of B is at 1500 nm. Considering them to be black bodies, what will be the ratio of the rate of total energy radiated by A to that of ?

•  9
•  9.5
•  8
•  8.5

Solution

Q133. The graph of elongation of rod of a substance A with temperature rise is shown in Figure. A liquid B contained in a cylindrical vessel made up of substance A, graduated in millitres at 0°C is heated gradually. The readings of the liquid level in the vessel corresponding to different temperatures are shown in the figure. The real volume expansivity of liquid is

•   2.7×10^(-5)/°C
•  15.4×10^(-5)/°C
•  16.2×10^(-5)/°C
•  151.2×10^(-5)/°C

Solution

Q134. It takes 10 min for an electric kettle to heat a certain quantity of water from 0°C to 100°C. It takes 54 min to convert this water at 100°C into steam. Then latent heat of steam is

•  80 cal/g
•  540 cal/kg
•  540 cal/g
•  80 cal/kg

Solution

Q135. A clock with a metal pendulum beating seconds keeps correct time at 0°C. If it loses 12.5 s a day at 25°C, the coefficient of linear expansion of metal of pendulum is

•  1/86400/°C
•  1/43200/°C
•  1/14400/°C
•  1/28800/°C

Solution
 135 (a) Loss of time due to heating a pendulum is given as ∆T=1/2 α∆θT ⇒12.5=1/2×α×(25-0)℃×86400s ⇒α=1/86400/℃

Q136. The loss in weight of a solid when immersed in a liquid at 0°C is W_0 and at t°C is W. If cubical coefficients of expansion of the solid and the liquid are γ_s and γ_L, respectively, then W is equal to

•  W_0 [1+(γ_s-γ_L)t]
•  W_0 [1-(γ_s-γ_L )t]
• W_0 [〖(γ〗_s-γ_L)t]
•  W_0 t[γ_s-γ_L]

Solution

Q137. A uniform solid brass sphere is rotating with angular speed ω_0 about a diameter. If its temperature is now increased by 100°C, what will be its new angular speed. (Given α_B=2.0×10^(-5) per °C)

•  1.1ω_0
•  1.01ω_0
•  0.996ω_0
•  0.824ω_0

Solution

Q138. A steel tape is placed around the earth at the equator. When the temperature is 0°C neglecting the expansion of the earth, the clearance between the tape and the ground if the temperature of the tape rises to 30°C, is nearly (α_steel=11×10^(-6)/K)

•  1.1 km
•  0.5 km
•  6400 km
•  2.1 km

Solution

Q139. Water falls from a height 500 m. The rise in temperature of water at bottom if whole of energy remains in water, will be (specific heat of water is c=4.2 kJ kg^(-1))

•  0.23℃
•  1.16℃
•  0.96℃
•  >1.02℃

Solution

Q140. A platinum sphere floats in mercury. Find the percentage change in the fraction of volume of sphere immersed in mercury when the temperature is raised by 80°C (volume expansivity of mercury is 182×10^(-6)/°C and linear expansivity of platinum is 9×10^(-6)/°C)

•  1.24%
•  1.38%
•  2.48%
• 2.76%

Solution