Thermal Properties of Matter-Quiz-4

 

THERMAL PROPERTIES OF MATTER QUIZ-4

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.

Q31. Two identical conducting rods are first connected independently to two vessels, one containing water at 100℃ and the other containing ice at 0℃. In the second case, the rods are joined end to end and connected to the same vessels. Let q_1 and q_2 〖gs〗^(-1) be the rate of melting of ice in the two cases respectively. The ratio q_1/q_2 is

•  1/2
•  2/1
•  4/1
•  1/4

Solution

32. As shown in Figure, AB is a rod of length 30 cm and area of cross section 1.0 cm^2 and thermal conductivity 336 SI units. The ends A and B are maintined at temperatures 20°C and 40°C, respectively. A point C of this rod is connected to a box D, containing ice at 0°C, through a highly conducting wire of negligible heat capacity. The rate at which ice melts in the box is (assume latent heat of fusion for ice L_f=80 cal/g)

•  84 mg/s
•  84 g/s
•  20 mg/s
•  40 mg/s

Solution

Q33. An ice box used for keeping eatables cool has a total wall area of m^2 and a wall thickness of 5.0 cm. The thermal conductivity of the ice box is K=0.01 J/m°C. It is filled with large amount of ice at 0°C along with eatables on a day when temperature is 30°C. The latent heat of fusion of ice is 334×10³ J/kg. The amount of ice melted in one day is (1 day =86,400 s)

•   776 g
•  7760g
•  11520 g
•  1552 g

Solution

Q34. T50 g of copper is heated to increase its temperature by 10°C. If the same quantity of heat is given to 10 g of water, the rise in its temperature is (specific heat of copper =420 J/Kg°C)

•  5°C
•  6°C
•  7°C
•  8°C

Solution

Q35. Three rods of identical cross-sectional area and made from the same metal form the sides of an isosceles triangle ABC right angled at B. The points A and B are maintained at temperature T and √2 T, respectively, in the steady state. Assuming that only heat conduction takes place, temperature of point C is

•  3T/(√2+1)
•  T/(√2+1)
•  T/(3(√2-1))
•  T/(√2-1)

Solution
 

Q36. A metal rod AB of length 10x has its one end A in ice at 0℃ and the other end B in water at 100℃. If a point P on the rod is maintained at 400℃, then it is found that equal amounts of water and ice evaporate and melt per unit time. The latent heat of evaporation of water is 540 cal/g latent heat of melting of ice is 80 cal/g. If the point P is at a distance of λx from the ice end A, find the value of λ. [Neglect any heat loss to the surrounding]

•  9
•  2
• 6
•  1

Solution

Q37. A thermometer has an ordinary glass bulb and thin glass tube filled with 1 mL of mercury. A temperature change of 1°C changes the level of mercury in the thin tube by 3 mm. The inside diameter of the thin glass is (γ_Hg=18×10^(-5)/°C, α_glass=10^(-5)/°C)

•  0.13 mm
•  0.25 mm
•  0.40 mm
•  0.50 mm

Solution

Q38. A brass rod and a lead rod each 80 cm long at 0°C are clamped together at one end with their free ends coinciding. The separation of free ends of the rods if the system is placed in a steam bath is (α_brass=18×10^(-6)/°C and α_lead=28×10^(-6)/°C)

•  0.2 mm
•  0.8 mm
•  1.4 mm
•  1.6 mm

Solution

Q39. Variation of radiant energy emitted by sun, filament of tungsten lamp and welding are as a function of its wavelength is shown in figure. Which of the following option is the correct match?

•  Sun-T_1, tungsten filament-T_2, welding arc-T_3
•  Sun-T_2, tungsten filament-T_1, welding arc-T_3
•  Sun-T_3, tungsten filament-T_2, welding arc-T_1
•  Sun-T_1, tungsten filament-T_3, welding arc-T_2

Solution

Q40. The length of a steel rod exceeds that of a brass rod by 5 cm. If the difference in their lengths remains same at all temperatures, then the length of brass rod will be: (α for iron and brass are 12×10^(-6)/°C and 18×10^(-6)/°C, respectively)

•  15 cm
•  5 cm
•  10 cm
• 2 cm

Solution