biomechanics 2

Which type of muscle contraction is used as a braking mechanism to1decrease the velocity of the arm after the ball has left your hand?

A eccentric
B concentric
C isotonic
D dynamic
E isometric

What is the function of a muscle acting as a neutralizer?

A prevents undesired joint rotation caused by the contracting muscles
B contracts to keep the two bones making up the joint from separating
C causes the opposite joint rotation to the one desired
D cooperates with other muscles to create the desired joint rotation

What is the function of a muscle acting as a stabilizer?

A causes the opposite joint rotation to the one desired
B cooperates with other muscles to create the desired joint rotation
C prevents undesired joint rotation caused by the contracting muscles
D contracts to keep the two bones making up the joint from separating

Which of the following illustrates eccentric muscle contraction of the hipextensors?

A bending forward with knees straight to touch the floor
B stepping up onto a bench
C holding a tennis racquet while awaiting a serve
D standing at attentionEnone of the above

In order to reduce "form drag," you should:

A increase fluid density
B reduce the surface roughness at higher velocities
C increase the relative velocity
D reduce the cross-sectional area
E all of the above

Which of the following statements is true of the Magnus force?

A It can created by a spinning ball
B It causes a ball to move up, down, left, or right
C It direction is always upward
D both A and B
E all of the above

A runner having an absolute velocity of +6 m/s is running on a windyday. The wind has an absolute velocity of +3 m/s. The relative velocity is ___

A 2 m/s
B 3 m/s
C 9 m/s
D 18 m/s
E none of the above

An object will float if ___

A it has a specific gravity > 1.0
B it has a density > 1000 kg/m3
C it has a buoyant force < 1000 N
D both A and B
E none of the above

A joint that allows uniaxial rotation of articulating bone surfaces arounda longitudinal axis is called

A a pivot joint
B a hinge joint
C a gliding joint
D an axial joint
E a twisting joint

A lever in the which the force acting on the lever is in between thefulcrum and the resistance is called a2

A 1st class lever
B 3rd class lever
C 2nd class lever

A joint that is "freely movable" and "highly mobile" would be classified as

A synovial and synarthrodial
B diarthrodial and fibrous
C synovial and diarthrodial
D synovial and amphiarthrodial
E diarthrodial and cartilaginous

The most stable triaxial joint is the . . .

A hip joint
B shoulderjoint
C knee joint
D elbow joint
E anklejoint

The forces that can influence the movement of a projectile are

A weight
B drag
C gravity
D both A and B
E all of the above

If the relative projection height is positive, which of the followingstatements is/are true?2

A horizontal displacement will decrease
B horizontal displacement will increase
C horizontal & vertical displacement will increase
D horizontal & vertical displacement will decrease

The optimal projection speed when relative projection height is zero willbe ___ meters/second.

A 40
B 45
C 50
D 55
E none of the above

Which of the following statements is/are true?

A As projection angle increases to 90 degrees, vertical displacement gets larger
B As projection angle increases to 90 degrees, vertical displacement gets smaller
C When projection angle is 45 degrees, vertical displacement reaches its maximumvalue
D both A and B
E none of the above