Elasticity

• What is the term for the force applied to bend an object?

  Bending force
• What happens when compressing forces are applied?

  They apply inward forces to an object
• How many forces are required to counterbalance each other in a stationary object?

  Two forces
• What must happen for an object to change shape?

  One force must be applied
• What occurs when the force is removed from an object within its elastic limit?

  The object remains in its original shape
• What is meant by elastic deformation?

  The object returns to its original shape
• When does plastic deformation occur?

  When the applied force exceeds the elastic limit
• What does Hooke's Law state about elastic objects?

  Extension is directly proportional to force
• What is the formula for Hooke's Law?

  $F =$$kx$
• What type of relationship exists when force is directly proportional to extension?

  Linear relationship
• What does a straight line through the origin on a graph indicate?

  Linear relationship between force and extension
• What characterizes a non-linear relationship in force-extension graphs?

  The graph arcs and deviates from a straight line
• What happens to energy when a spring is stretched or compressed?

  It is stored as elastic potential energy
• What is the formula for elastic potential energy?

  $E_p =$$\frac{1}{2} k e^2$
• How can the spring constant be calculated?

  Using Hooke's Law
• What is the first step in the required practical for investigating force extension for a spring?

  Set up the apparatus with the spring suspended
• How do you calculate the extension of the spring?

  Subtract the initial length from the new length
• What should you do after measuring the extension for different weights?

  Plot a graph of force against extension
• What does a curved graph beyond the limit of proportionality indicate?

  Non-linear relationship between force and extension