Searle’s apparatus is used for the measurement of Young’s modulus. It consists of two equal-length wires that are attached to a rigid support. To understand how Searle’s apparatus is used to determine Young’s modulus of elasticity of the material of a given wire, read the experiment below.

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## What is the principle of Searle’s method?

Searle’s method in calculation of thermal conductivity k is the coefficient of thermal conductivity of the bar. where Cw is the specific heat of water, m is the mass of water collected during time t, Twater is difference in the temperature of water before and after it has gone through the bar.

## What is the major source of error in Searle’s experiment?

The main source of error is the loss of heat along the length of the bar to the surroundings.

## Who invented Searle’s apparatus?

1.0 Introduction. George Frederick Charles Searle was born December 3rd, 1864 and was a British Physicist and Lecturer.

## How does Searles apparatus work?

Searle’s Apparatus Both control and test wires are connected to a horizontal bar at the other ends. A spirit level is mounted on this horizontal bar. Now, this bar is hinged to the control wire. If we increase the weight on the side of test wire, it gets extended and causes the spirit level to tilt by a small amount.

## What is SI unit of thermal conductivity?

The SI unit of thermal conductivity is watts per meter-kelvin (Wm-1K-1).

## Why does a thick rod used in Searle’s method?

Due to the insulation of the rod, no heat is lost due to surroundings. At a steady-state, at every cross-section of the rod, the quantity of heat entering the section in one second is equal to the quantity of heat leaving the section due to conduction.

## Is Searle method applicable for bad conductor?

Explanation: The most commonly used methods are Searle’s method and Lee’s disc method, for good and bad conductors of heat, respectively.

## How do you measure thermal conductivity?

It is most often used in physics and is useful in determining how a material conducts electricity. To measure thermal conductivity, use the equation Q / t = kAT / d, plug in your area, time, and thermal constant, and complete your equation using the order of operations.

## What is Searle’s apparatus for thermal conductivity?

Searle’s apparatus for determination of thermal conductivity. It consists of a metallic rod having two gaps is known as the distance of separation. The rod is heated by circulating stem and next is cooled by circulating cold water.

## How do you calculate Young’s modulus of steel?

## How you can determine the Young’s modulus of a wire by Searle’s apparatus explain?

Young’s modulus of wire material is given by, Y=stressstrain=F/Al/L=4FLฯd2l. From given data, F=mg=9.8N, L=2.0m, l=0.8ร10โ3m, and d=0.4ร10โ3m. Substitute the values in equation to get Y=1.95ร1011โ2.0ร1011N/m2.

## How do you calculate practical Young’s modulus?

- Calculate the cross-sectional area of the wire. The area of circle is given by:
- Plot a graph of load (force) against extension.
- Determine the gradient of this graph.
- Multiply the gradient by the ratio of the original length and cross-sectional area of the wire to calculate the Young Modulus.

## How does thermal conductivity depend on temperature?

The thermal conductivity of liquids decreases with increasing temperature as the liquid expands and the molecules moves apart. While in solids, the thermal conductivity decreases at higher temperatures due to the anharmonic scattering which is inversely proportional to the temperatures changes.

## How do you spell Searle?

Searle Definition & Meaning | Dictionary.com.

## Why are 2 wires used in Young’s modulus?

Two wires are used to eliminate errors due to changes of temperature and sagging of the beam.

## How do you calculate Young’s modulus of elasticity?

Sometimes referred to as the modulus of elasticity, Young’s modulus is equal to the longitudinal stress divided by the strain. Stress and strain may be described as follows in the case of a metal bar under tension. Young’s modulus = stress/strain = (FL0)/A(Ln โ L0).

## What is Young’s modulus apparatus?

Holmarc’s Young’s modulus apparatus (Model No: HO-ED-M-02) is used to measure the Young’s modulus of a bar. Young’s modulus is a measure of stiffness of an elastic material and is a quantity used to characterize materials. It can vary considerably depending on the exact composition of the material.

## What is K value in thermal conductivity?

K-value is simply shorthand for thermal conductivity. The ASTM Standard C168, on Terminology, defines the term as follows: Thermal conductivity, n: the time rate of steady state heat flow through a unit area of a homogeneous material induced by a unit temperature gradient in a direction perpendicular to that unit area.

## What is the symbol for thermal conductivity?

Thermal conductivity refers to the ability of a given material to conduct/transfer heat. It is generally denoted by the symbol ‘k’ but can also be denoted by ‘ฮป’ and ‘ฮบ’. The reciprocal of this quantity is known as thermal resistivity.

## What factors affect thermal conductivity?

At the macroscopic level, thermal conductivity largely depends on three main factors: operating temperature, moisture content, and density [33,37,42]. Other factors are a thickness, pressure, air surface velocity, and aging.

## What is the thermal conductivity of bad conductor?

To determine thermal conductivity of a bad conductor (glass) in form of a disc using Lee’s method. where H is the steady state rate of heat transfer, k is the thermal conductivity of the sample, A is the cross sectional area and (T 2 โ T1) is the temperature difference across the sample thickness ‘x’ (see Fig.

## How do we measure the rate of water flow through the spiral in Searle’s bar method?

Measure the rate of water flow through the spiral by measuring the amount of water (m) collected in the measuring cylinder in a given time (t). Collect approximately 1 litre. Using Vernier callipers, measure the diameter of the bar D and the distance d between the thermometers T1 and T2.

## Why steam is used instead of hot water in Lee’s disc experiment?

This steam causes the metal disc to heat up and transfer heat to the poor conductor that is being tested. The poor conductor in turn transfers heat to the bottom metal disc, which loses heat to convection.

## Why should a bad conductor be thin?

With a poor conductor the rate of flow of heat will be small and so a thin specimen with a large cross-sectional area has to be used.