Biomechanics

    Biomechanics
    In cars, the aim of safety features, such as seatbelts, padding on the dashboard, collapsible steering columns, airbags and body panels that crumple progressively, is to minimise the unbalanced force on occupants during a crash. Bearing Newton’s second law in mind, how do such features achieve this? They:
    Say the occupant has a mass of “m”. Newton’s second law states F = m × a to make the unbalanced force F as small as possible, and then the acceleration “a” must be made small. Acceleration may be positive or negative; the latter is often called a “deceleration”.
    Author: rikazzz Comment
    Biomechanics
    Third-class lever systems are always inefficient for which one of the following reasons?
    By definition of third-class levers, the load arm is always longer than the effort arm. A spanner tightening a nut has a long effort arm and is a mixture of first- and second-class lever.
    Author: rikazzz Comment
    Biomechanics
    When the biceps brachii muscle flexes the forearm, what is the forearm an example of?
    Third-class levers have the effort force between the fulcrum and the load.
    Author: rikazzz Comment
    Biomechanics
    What does the term “friction” refer to?
    Friction is a force that causes a moving object to slow in speed. That is, it produces a negative acceleration – one in the opposite direction to the object’s velocity.
    Author: rikazzz Comment
    Biomechanics
    Traction forces may be represented by vectors. In Hamilton-Russell traction, which of the following vectors is equal in magnitude to the traction force?
    By elevating the foot of the bed, the patient tends to slide towards the head of the bed which is opposite to the direction of traction pull.
    Author: rikazzz Comment
    Biomechanics
    What is the purpose of using a slide sheet in patient manual handling?
    A slide sheet reduces friction, making it easier to slide the patient. It also provides comfortable handholds and prevents fragile skin being torn as it slides along the bed.
    Author: rikazzz Comment
    Biomechanics
    Which of the following is not an example of a force?
    Inertia is not a force; it is a measure of mass. A measure of inertia of an object is the difficulty of setting the object in motion.
    Author: rikazzz Comment
    Biomechanics
    When two forces of magnitude 6 N and 10 N are added vectorially, what value could the resulting vector NOT have?
    The maximum value that can be obtained by adding two vectors of length 6 and 10 N is 16 N when the vectors are in the same direction.
    Author: rikazzz Comment