Heat current can be defined as the rate at which the heat is transferred per unit time. As it is the rate of energy over time, so it is represented in the SI unit of joule per second or Watt(W). Heat is something that flows through objects with help of conduction imparting energy to the neighbouring particles.

The rate of flow of heat through a copper rod with temperature difference 30 ° C is 1500 c a l / s . Find the thermal resistance of copper rod.

Given that, d Q d t = 1500 c a l / s ∆ T = 30 ° C = 30 K We know that, d Q d t = ∆ T R t h ⇒ 1500 = 30 R t h ⇒ R t h = 30 1500 ⇒ R t h = 0 . 02 K s / c a l Hence, thermal resistance is 0 . 02 K s / c a l .

EASY

Earn 100

Define heat current.

Important Questions on Thermal Phenomena

MEDIUM

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

What is thermal conductivity? What is its SI unit?

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

State whether the following statement is true or false:
“The constituent particles of a material change position during conduction of heat through it.”

MEDIUM

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

Explain the term 'steady state'.

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

In Ingen Hausz experiment, _____ of different materials is obtained.

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

K =

thermal conductivity, the value of thermal resistivity

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

Explain the term thermal resistance. State its SI unit arid dimensions.

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

A rod of length

ℓ

and cross section area

A

has a variable thermal conductivity given by

k = α T

, where

α

is positive constant and

T

is temperature in kelvin. Two ends of the rod are maintained at temperatures

T_{1}

and

T_{2} (T_{1} > T_{2})

. Heat current flowing through the rod will be

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

The rate of flow of heat through a copper rod with temperature difference

30 ° C

1500 c a l / s

. Find the thermal resistance of copper rod.

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

For an ideal _____ thermal conductivity is infinite.

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

Name the non-metal which helps in conduction of heat.

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

The rods used in Ingen Hausz experiment were made of different material, same _____ and polish to obtain same emissivity.

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

In case of an ideal insulator, the thermal conductivity

K

EASY

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

Find the odd one out:

HARD

Physical Science>Physics>Thermal Phenomena>Thermal Conduction

A conducting cylindrical rod of uniform cross-sectional area is kept between two large chambers which are at temperatures $100 ° C$ and $0 ° C$ , respectively. The conductivity of the rod increases with $x$ , where $x$ is distance from $100 ° C$ end. The temperature profile of the rod in steady-state will be as:

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