Robert Hooke Hooke’s Law deals with springs.
Enduring Understanding: The ability to quantify (measure) force has important social impacts. Essential Question: How can force be quantified? Essential Question: What types of forces may be quantified? Essential Question: What else can be determined once forces are quantified?
Hooke’s Law Vocabulary Elasticity: An object that compresses or expands when a force is applied but returns to its original shape when the force is removed. Elongation: The stretching distance of an object that displays elasticity.
Elastic Limit: When an object that displays elasticity has an elongation past its elastic limit, it will no longer return to its original shape.
Hooke’s Law: When a force is applied to an object that displays elasticity (ex. Spring), the elongation or compression is directly related to the size of the force.
F = kx F : the force applied to the spring x : the elongation or compression distance k : a spring constant that depends on the spring
How could knowing a spring’s constant be useful?
A spring is stretched 10 m and the force was 20 N. What is the spring constant? 2 N/m
A spring with a proportionality constant of 0.40 N/m is stretched 15 m. What was the force? 6 N
A 5.0 kg mass is hung from a spring with a spring constant of 200 N/m. What is the elongation?.25 m Remember, it is the weight that supplies the force. F = mg = (5)(9.8) = 49 N