hooke’s law. sir robert hooke (1635-1703) english biology: “cell”, evolution chemistry:...
TRANSCRIPT
HOOKE’S LAW
SIR ROBERT HOOKE (1635-1703)
• English• Biology: “cell”,
evolution• Chemistry: vacuum,
Boyle’s law• Physics: Refraction and
wave theory of light, gravity, law of elasticity
Law of Elasticity: “Hooke’s Law”F= -kx
• F = restoring force of spring
• x = the distance that the spring has been stretch or compressed from equilibrium
• k = the spring constant• (-) = force acts in
opposite direction of the displacement
Lab Activity p 255
• Prepare a data table:Mass (kg) Applied Force (N) =Fg Extension of Spring (m)
0.0000.2000.4000.6000.8001.000
0 N 0m = equilibrium
Lab Activity p 255
• Gather: a ring stand, meter stick, spring, tape, set of masses (100g, 2 x 200g, 500g, 1kg)
• Attach the meter stick to a desk or lab bench• Hang the spring on the ring stand and
position it such that the end of the spring with no mass attached is lined up with the ZERO
• Hang masses and record the extension
Lab Activity p255
• Create a graph of the applied force vs the extension. – NOTE: put the extension on the x-axis and the force
on the y-axis• QUESTIONS:1)Describe the shape of the graph. What is the
relationship between the extension and the applied force?
2)Determine the equation of the graph. What does the slope represent?
ELASTIC POTENTIAL ENERGY• You can use the graph of Hooke’s Law to
determine the quantity of potential energy stored in the spring.– Calculate the area under the force vs position
graph
EP = ½ kx2