| |1. A spring is 20 cm long when a load of 10 N is hanging from it, and 30 cm long when a load of 20 N is hanging from it. Draw a graph to work out the length of the spring when:

a] there is no load on it;

b] there is a load of 5 N on it.

(Plot x = load, y = spring length)

2. In a spring experiment, the results were:

|load (N) |0 |1 |2 |3 |4 |5 |6 |7 |

|length (mm) |50 |58 |70 |74 |82 |90 |102 |125 |

|extension (mm) | | | | | | | | |

a] What is the length of the spring when unstretched?

b] Copy and complete the table.

c] Plot a graph of the data. (Plot x = load, y = spring extension)

d] One of the results is wrong.

(i) Which? (ii) What should the result be?

e] Mark the elastic limit on your graph.

f] What load would give an extension of 30 mm?

g] What would be the spring length for a load of 4.5 N?

3. Some students carry out an experiment to find out how a spring stretched when loads were added to it.

a] Draw a labelled diagram to show what is meant by the extension of the spring.

The results of the experiment are shown in the table. One of the readings is incorrect.

|load (N) |0 |2 |4 |6 |8 |10 |12 |14 |

|extension (mm) |0 |16 |32 |58 |64 |80 |96 |112 |

b] Use these results to plot a graph. (Plot x = load, y = spring extension)

c] Use your graph to find (i) the extension when the load is 3 N;

(ii) the load which produces and extension of 40 mm.

d] Label the incorrect point on the graph with the letter E.

4. (EXTENSION) An engineer needs to know how far a long beam will sag under a load. The table shows some results:

|load (N) |1000 |2000...