When is given to a body the particles of body or atoms starts oscillations.For a particle who comes back to its original position when this applied force because of heat is removed ,potential energy curve is symmetric.
But the general tendency of this potential energy curve is asymmetric and atoms are unable to come back to their original positions. This inter atomic distance increases and this is called thermal expansion.
The magnitude of expansion depends inversely on the force of attraction between the atoms of body. Thus the solids expands least, liquids ten to hundred times more (approximately) and gases expansion is much more.
A solid expands along three dimensions and they are called linear,areal and volume expansions.They are correspondingly measured with coefficients. These coefficients depends on the nature of materiel and independent of physical dimensions and temperature given to the body.
Most substances expand on heating and contract on cooling. A change in the temperature of a body causes change in its dimensions. The increase in the dimensions of a body due to the increase in its temperature is called thermal expansion.
The expansion in length is called linear expansion. The expansion in area is called area expansion. The expansion in volume is called volume expansion .
If the substance is in the form of a long rod, then for small change in temperature, ΔT, the fractional change in length, Δl/l, is directly proportional to ΔT. The proportionality constant is called linear expansion coefficient.
Similarly we can define areal and volume expansion coefficients.
Other useful topics in physics
Heat and Temperature
Surface energy and tension
Viscosity
Dynamic lift
Venturi meter
Torricelli's theorem
Blood flow and heart attack
Stream line flow
What is pressure ?
Pressure variation with depth
Pascal's Law
But the general tendency of this potential energy curve is asymmetric and atoms are unable to come back to their original positions. This inter atomic distance increases and this is called thermal expansion.
The magnitude of expansion depends inversely on the force of attraction between the atoms of body. Thus the solids expands least, liquids ten to hundred times more (approximately) and gases expansion is much more.
A solid expands along three dimensions and they are called linear,areal and volume expansions.They are correspondingly measured with coefficients. These coefficients depends on the nature of materiel and independent of physical dimensions and temperature given to the body.
Most substances expand on heating and contract on cooling. A change in the temperature of a body causes change in its dimensions. The increase in the dimensions of a body due to the increase in its temperature is called thermal expansion.
The expansion in length is called linear expansion. The expansion in area is called area expansion. The expansion in volume is called volume expansion .
If the substance is in the form of a long rod, then for small change in temperature, ΔT, the fractional change in length, Δl/l, is directly proportional to ΔT. The proportionality constant is called linear expansion coefficient.Similarly we can define areal and volume expansion coefficients.
Other useful topics in physics
Heat and Temperature
Surface energy and tension
Viscosity
Dynamic lift
Venturi meter
Torricelli's theorem
Blood flow and heart attack
Stream line flow
What is pressure ?
Pressure variation with depth
Pascal's Law
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