Edexcel A (SNAB) A Level Biology:复习笔记4.2.7 Practical: Determining the Tensile Strength of Plant Fibres

• The tensile strength of a fibre refers to the maximum load it can carry before breaking
  • For example, this information would be important when determining the strength of a rope made of plant fibres

Apparatus

• Plant fibres
• Retort stand (clamp stand)
• Clamp
• Weights

Method

• The fibre should be attached to a clamp stand
• Attach a weight on the other end of the plant fibre
• Carefully continue to add one weight at a time until the fibre breaks
• Record the mass at which the fibre broke
• This represents the tensile strength
• To increase the accuracy of your results, this process should be repeated with more samples of the same plant fibre
  • These values can be used to calculate the mean tensile strength for the fibre
  • It is important to ensure that the fibres are all of the same length and that all other variables are kept constant

Apparatus used to determine the tensile strength of plant fibres