In stretching a wire work is done against internal restoring forces. This work is stored as elastic potential energy or strain energy. If a force F acts along the length L of the wire or cross section A and stretches it by x then: **Young′sModulus(Y)=StressStrain=F/Ax/L=FLAx⇒F=YALx**.

Contents

- 1 Is there a work done stretching?
- 2 How do you find the work of a stretched spring?
- 3 How do you calculate work done in elasticity?
- 4 Why work is required to be done to stretch a wire?
- 5 In which form is the work done in stretching a wire is stored as?
- 6 What happened to rubber bands?
- 7 How do you calculate work done?
- 8 What is the work done on a spring?
- 9 What is work done in stretching a wire?
- 10 How do you calculate electrical work?
- 11 How do you calculate work done by Young’s modulus?
- 12 What would happen to the resistance of a wire if it is stretched to double its length?
- 13 When a wire is bent back and forth it becomes hot Why?

## Is there a work done stretching?

Work done by Stretching of a Spring: If a spring is stretched, the direction of applied force and the direction of displacement are the same. And the angle between the force and the displacement is zero, which results in the positive work done by the stretching force.

## How do you find the work of a stretched spring?

The average force you exert as you change the displacement from 0 to x is ½kx. The work you do when stretching or compressing a spring a distance x from its equilibrium position therefore is W = ½kx^{2}.

## How do you calculate work done in elasticity?

Energy stored in a spring

- Work is done when a spring is extended or compressed. Elastic potential energy is stored in the spring.
- The elastic potential energy stored can be calculated using the equation:
- elastic potential energy = 0.5 × spring constant × (extension)
^{2}

## Why work is required to be done to stretch a wire?

When we stretch a wire, the work has been done against interomic forces. This work is stored in the wire in the form of elastic potential energy.

## In which form is the work done in stretching a wire is stored as?

Thus total work done in stretching the wire gets stored in the form of its elastic potential energy. It is sometimes called strain energy.

## What happened to rubber bands?

It changes shape when extended and returns to its original shape when the applied force is withdrawn. That is why, after being a solid, a rubber band changes shape. Furthermore, if too much stress is applied, the rubber band will snap.

## How do you calculate work done?

Work can be calculated with the equation: Work = Force × Distance. The SI unit for work is the joule (J), or Newton • meter (N • m). One joule equals the amount of work that is done when 1 N of force moves an object over a distance of 1 m.

## What is the work done on a spring?

The area under the force in the spring vs. displacement curve is the work done on the spring. Figure 1 shows a plot of force on the spring vs. displacement, where displacement is 0 when the spring is unstretched.

## What is work done in stretching a wire?

In stretching a wire work is done against internal restoring forces. This work is stored in the wire as elastic potential energy or strain energy. This work done is stored in the wire. Dividing both sides by volume of the wire we get energy stored in unit volume of wire.

## How do you calculate electrical work?

So if 1 watt = 1 joule per second, it therefore follows that: 1 Joule of energy = 1 watt over one unit of time, that is: Work equals Power multiplied by Time, (V*I*t joules). So electrical energy (the work done) is obtained by multiplying power by the time in seconds that the charge (in the form of a current) flows.

## How do you calculate work done by Young’s modulus?

Find the work done in stretching a wire of length 2 m and of sectional area 1 mm² through 1 mm if Young’s modulus of the material of the wire is 2 × 10^{11} N/m². Given: Area = A = 1 mm² = 1 × 10^{–}^{6} m², Length of wire = L = 2m, Extension in wire = l = 1mm = 1 × 10^{–}^{3} m, Young’s modulus = Y =2 × 10^{11} N/m².

## What would happen to the resistance of a wire if it is stretched to double its length?

As the length of wire gets doubled, the cross-sectional area will become half of its previous value because volume of wire remains constant. Hence, we can see that the new resistance is four times the previous resistance.

## When a wire is bent back and forth it becomes hot Why?

When a wire is bent back and forth, heat is generated due to the area of the elastic hysteresis and frictional force. Hence it becomes hot. 12.