Physics

Thermal Properties and Thermodynamics

380 Questions

Thermal properties and thermodynamics questions evaluate concepts of heat transfer, thermal efficiency, and temperature variations. Problems involve calculating heat content, conductivity, and the performance of heat engines. This subject is regularly tested in physics sections across multiple competitive platforms.

Heat transfer calculationsThermal efficiencyBlack body radiationTemperature variationsRefrigeration performance

Thermal Properties and Thermodynamics Questions

Multiple choice solid waste management environmental management biology

Incineration is performed at

  1. High temperature more than 1000$^o$ C

  2. 273K
  3. Temperature lower than 200$^o$ C
  4. 0$^o$ C
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials at very high temperatures, typically above 1000 degrees Celsius.

Multiple choice physics electromagnetic forces oersted experiment oersted's experiment magnetic field due to a straight current carrying conductor

Thermistors have ________

  1. positive temperature coefficient

  2. negative temperature coefficient

  3. zero temperature coefficien

  4. infinite temperature coefficient
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Thermistor generally has a negative temperature coefficient of resistance. With increase in temperature, resistance of a thermistor decreases.

Multiple choice zoology human population population ecology population size population and how it changes

Volume and surface area of a deer is 1,50,000 c$m^3$ and 19,000 c$m^2$ and of a squirrel is 625 c$m^3$ and 530 c$m^2$. The area available for heat loss per c$m^3$ of squirrel will be approximately

  1. Seven times more than the deer

  2. Eleven times less than the deer

  3. Three times more than the deer

  4. Eleven times more than the deer
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Surface area to volume ratio determines heat loss. For deer: 19000/150000 = 0.126. For squirrel: 530/625 = 0.848. Ratio 0.848 / 0.126 is approximately 6.7, which is close to 7.

Multiple choice physics energy and its forms idea of energy introduction to work and energy work and energy

Work required to produce $1000   k$ - calorie heat will be

  1. $4.2 Joule$
  2. $0.42 \times {10}^{6} Joule$
  3. $4.2 \times {10}^{6} Joule$
  4. $4.2 \times {10}^{7} Joule$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In this problem, we have to convert the heat energy in unit from calorie to Joule. 

According to work-energy theorem, the work is also a energy. 
Thus, $1000k.cal=1000\times 10^3 cal=10^6 cal=4.2\times 10^6 J$  (as $1 cal=4.2 J$)

Multiple choice chemistry change around us physical changes changes and their classification physical changes

An iron ball at $\displaystyle { 50 }^{ \circ  }C$ is dropped in a beaker of water at $\displaystyle { 50 }^{ \circ  }C$. The heat will 

  1. Not flow from iron ball to water

  2. Not not flow from iron ball to water or from water to iron ball

  3. Not flow from water to iron ball

  4. Increase the temperature of both
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Energy flows always from a higher temperature to lower temperature. In this case there is no temperature  difference hence energy would not flow in any way.

Multiple choice physics semiconductors band theory of solids, a brief introduction electron energies in solids energy bands

The energy gap $E _G$ of a semi-conductor decreases with rise in temperature.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

As the temperature is increased, the thermal energy to the electron within the semiconductor material also increases. Therefore, now lower energy is required to break the bond. This reduction in Bond energy also reduces the band gap. So, the band gap of a semiconductor decreases with increasing temperature.