Advertisements
Advertisements
प्रश्न
Write down the expression for the elastic potential energy of a stretched wire.
Advertisements
उत्तर
The work done in stretching the wire by dl,
dW = F.dl
The total work done in stretching the wire from 0 to l is
W = `int_0^"l" "F"."dl"` ..........(1)
From Young’s modulus of elasticity, force becomes,
Y = `"F"/"A" xx "L"/"l" = "YAl"/"L"` ........(2)
Substituting equation (2) in (1) we get,
W = `int_0^"l" "YAl"/"L" "dl"`
Since l is the dummy variable in the integration, we can change l to lʹ(not in limits).
Therefore W = `int_0^"l" "YAlʹ"/"L" "dlʹ" = "YA"/"L"["lʹ"^2/2]_0^"l" = "YA"/"L" "l"^2/2 = 1/2["YAl"/"L"] "l" = 1/2 "Fl"`
W = `1/2` Fl
This work done is known as the elastic potential energy of a stretched wire.
APPEARS IN
संबंधित प्रश्न
Consider two wires X and Y. The radius of wire X is 3 times the radius of Y. If they are stretched by the same load then the stress on Y is ___________.
The load-elongation graph of three wires of the same material as shown in the figure. Which of the following wire is the thickest?

Two wires are made of the same material and have the same volume. The area of cross-sections of the first and the second wires are A and 2A respectively. If the length of the first wire is increased by ∆l on applying a force F, how much force is needed to stretch the second wire by the same amount?
The Young’s modulus for a perfect rigid body is __________.
Which of the following is not a scalar?
If the temperature of the wire is increased, then Young’s modulus will __________.
The following four wires are made of the same material. Which of these will have the largest extension when the same tension is applied?
Define Poisson’s ratio.
Which one of these is more elastic, steel or rubber? Why?
Explain the different types of modulus of elasticity.
