Forces & Elasticity Practice Questions

Explain why more than one force is needed to stretch the exercise band.

When the student lets go, the band returns to its original length.

State the name given to this type of distortion.

The student then pulls the band much harder. When he lets go, the band is longer than it was at the start.

State the name given to this type of distortion.

Calculate the spring constant of the spring.

spring constant = ............................................... N/m

A different suitcase of weight $9.0$ N is hung from the same scales.

Calculate the extension of the spring.

extension = ............................................... m

Use the graph to calculate the spring constant of the spring.

spring constant = ............................................... N/m

State the force at which the limit of proportionality of the spring is reached and explain how the graph shows this.

The area between the line of a force–extension graph and the extension axis is equal to the work done in stretching the spring.

Calculate the work done in stretching the spring from zero extension to the extension at point P.

work done = ............................................... J

Calculate the energy transferred to the spring when it is compressed by $5.0$ cm.

Use an equation selected from the list of equations at the end of this paper.

energy transferred = ............................................... J

A child compresses the same spring by $10.0$ cm instead.

State how many times greater the energy stored in the spring now is, and explain your answer.

Calculate the spring constant of the spring.

Use an equation selected from the list of equations at the end of this paper.

spring constant = ............................................... N/m

Calculate the force the athlete applies to the spring when its extension is $0.60$ m.

force = ............................................... N

Describe a method the student could use to obtain the measurements needed to plot a graph of force against extension.

Explain why the student must measure the length of the spring before she adds any weights.

Show that the energy stored in the spring when its extension is $0.40$ m is about $2$ J.

Use an equation selected from the list of equations at the end of this paper.

The spring is stretched further, so that its extension increases from $0.40$ m to $0.60$ m.

Calculate the additional work done in stretching the spring from $0.40$ m to $0.60$ m.

additional work done = ............................................... J

Explain why more work is done stretching this spring from $0.40$ m to $0.60$ m than from $0$ m to $0.20$ m.

Explain how the loading results show that the relationship between force and extension for this cord is non-linear.

State the name given to the type of distortion shown by the cord and give the evidence from the table that supports your answer.

The work done by the student in stretching the cord is $24$ J. As the cord is unloaded it does $19$ J of work.

Calculate the energy dissipated by the cord and state the energy store it is transferred to.