OCR B P 6.3 Hooks Law and Extension Quiz

The graph of load (force) against extension is for a steel spring. The original length of the spring
was 8 cm. Calculate the spring constant of the spring in N/cm.

The graph of load (force) against extension is for a steel spring. The original length of the spring
was 8 cm. Using the value for spring constant from question 1 to predict the extension for a load of 10 N.

A steel spring 20 mm long stretches to 40 mm when a 100 g mass is suspended from it.

a- What is the extension of the spring in cm?

b- What force is provided by the weight of the 100 g load?

c- Calculate the spring constant in N/cm.

d- What load would be required to give an extension of 25 mm?

A spring 18 cm long stretches to 62 cm with a load of 200 g.

a -Calculate the spring constant in N/m. Give your answer to 2 significant figures.

b- What is the length of the spring for a load of 100 g?

The springs in a bed mattress are 15 cm high. They compress when someone sits or
lies on the mattress. The spring constant of such a spring is about 5 kN/m.

a- What force would be needed to cause a compression of 1 cm?

b- How much would the spring compress if the force on the spring were 70 N? Give your answer in m, expressed in standard form.

A steel spring with spring constant 4.5 N/m is stretched from 18 cm to 58 cm. Calculate the energy stored in the spring.

a- Write down what you know with the units. Convert to standard units.

b- Write down the equation you will use to calculate the energy stored in a spring that obeys Hooke’s law.

Substitute the quantities into the equation and calculate the energy stored in the spring.

Two students are investigating springs and forces.

They begin by comparing three different springs.

They measured how much each spring stretched for a range of different weights attached.

One of the students makes a comment about the data. Is this student correct?

Use your understanding of what is meant by a linear relationship to help explain your answer.

Two students are investigating springs and forces. They begin by comparing three different springs.

They measured how much each spring stretched for a range of different weights attached.They then plotted a graph of the data for spring C. (Note that the extension of the spring is in metres).

Use the graph to calculate the amount of work done (in joules) in stretching the spring over the first 8 cm (0.08 m).