musculoskeletal levers

Question 1

what is a lever?

Answer 1

a rigid structure hinged at one point and to which forces are applied to (at least) two other points

Question 2

what does a lever system require?

Answer 2

a rigid bar, a fulcrum (hinge), an applied force, and a resistance

Question 3

what are the two functions of levers?

Answer 3

to increase the effect produced when a force is exerted on an object, and to increase the speed with which an object can be moved

Question 4

what are the 3 classes of levers?

Answer 4

first class, second class, and third class

Question 5

describe a first class lever

Answer 5

the fulcrum is found between the force and the resistance

Question 6

describe a second class lever

Answer 6

the resistance is found between the fulcrum and the force

Question 7

describe a third class lever

Answer 7

the force is found between the fulcrum and the resistance

Question 8

what is mechanical efficiency?

Answer 8

the efficiency of a lever system/how much force is needed to overcome a given resistance

Question 9

what does it mean if the mechanical efficiency is larger than 1?

Answer 9

the effort force required is reduced

Question 10

what does it mean if the mechanical efficiency is smaller than 1?

Answer 10

the speed of movement is increased

Question 11

in the human body, what makes up a lever system?

Answer 11

bone (rigid bar), joint centre (fulcrum), muscle action (applied force), and external load (resistance)