THERMAL PHYSICS QUIZ-3

THERMAL PHYSICS QUIZ-3

Dear Readers,

As per analysis for previous years, it has been observed that students preparing for NEET find Physics out of all the sections to be complex to handle and the majority of them are not able to comprehend the reason behind it. This problem arises especially because these aspirants appearing for the examination are more inclined to have a keen interest in Biology due to their medical background. 

Furthermore, sections such as Physics are dominantly based on theories, laws, numerical in comparison to a section of Biology which is more of fact-based, life sciences, and includes substantial explanations. By using the table given below, you easily and directly access to the topics and respective links of MCQs. Moreover, to make learning smooth and efficient, all the questions come with their supportive solutions to make utilization of time even more productive. Students will be covered for all their studies as the topics are available from basics to even the most advanced. 

Q1. In a room where the temperature is 30℃, a body cools form 61℃ to 59℃ in 4 min. The time (in minutes) taken by the body to cool from 51℃ to 49℃ will be

•  8
•  5
•  6
•  4

Solution

Q2.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

Q3.  A block of mass 100 gm slides on a rough horizontal surface. If the speed of the block decreases from 10 m/s to 5 m/s, the thermal energy developed in the process is

•   3.75 J
•  37.5 J
•  0.375 J
•  0.75 J

Solution

Q4. Water falls from a height of 500 m. What is the rise in temperature of water at the bottom if whole energy is used up in heating water?

•  0.96℃
•  1.02℃
•  1.16℃
•  0.23℃

Solution

Q5.Two rigid boxes containing different ideal gases are placed on a table. Box A contains one mole of nitrogen at temperature T0, while box B contains one mole of helium at temperature 7/3T0. The boxes are then put into thermal contact with each other and heat flows between them until the gases reach a common final temperature (Ignore the heat capacity of boxes). Then, the final temperature of the gases, Tf, in terms of T0 is

•  Tf=73T0
•  Tf=32T0
•  Tf=52T0
•  Tf=37T0

Solution
 

Q6. The energy emitted per second by a black body at 27℃ is 10 J. If the temperature of the black body is increased to 327℃, the energy emitted per second will be

•  20 J
•  40 J
•  80 J
•  160 J

Solution

Q7.The temperature of hot and cold end of a 20cm long rod in thermal steady state are at 100℃ and 20℃ respectively. Temperature at the centre of the rod is

•  50℃
•  60℃
•  40℃
•  30℃

Solution

Q8.Oxygen boils at -183℃. This temperature is approximately

•  215oF
•  -297oF
•  329oF
•  361oF

Solution

Q9.A hot liquids is filled in a container and kept in a room of temperature of 25℃. The liquid emits heat at the rate of 200Js-1. When its temp. is 75℃. When the temperature of the liquid becomes 40℃, the rate of heat loss in Js-1 is

•  160
•  140
•  80
•  60

Solution

Q10. A steel wire of uniform area 2 mm2 is heated up to 50℃ and is stretched by tying its ends rigidly. The change in tension when the temperature falls from 50℃ to 30℃ is (Take Y=2×1011Nm-2, α=1.1 ×10-5℃-1)

•  1.5 1010 N
•  5 N
•  88 N
•  2.5 1010 N

Solution