Exam Qs Flashcards
During running, the relative ankle angle at ground contact for heel-toe runner (rear-foot striker) is typically in the region of….
90 degrees
Angular acceleration can be described as…
Rate of change of angular velocity w/ respect to time.
If a gymnast on a high bar starts from handstand + swings 1 complete revolution + finishes in a handstand, what’s the gymnasts angular displacement?
0 degrees.
A sprinter is filmed in the sagittal plane moving from left to right + joint centres for the right leg are recorded in 2D in the following position (cm relative to the origin): hip (6,105); knee(33,49); Ankle (6,13).
Using this info, calculate the knee-angle - the convention for which, is described as follows: knee angle defined behind the back of the knee where the min angle represents max knee flexion.
117.4 degrees
What do heel inserts do the ankle angle and what does that result in?
Heel inserts ⬆️ ankle angle = ⬇️ ankle dorsi-flexion
Suggesting ⬇️ un Achilles Tendon Strain
A hammer thrower starts facing the back of the circle + rotates 3.5 times before releasing the hammer at the front of the circle.
They take 1.5 secs to complete 3.5 revolutions.
What is their average angular velocity?
120 deg/s
Supination is characterised by simultaneous…
Inversion
Plantar-flexion
Adduction
The magnitude of peak eversion during running for a heel-toe runner (rear-foot striker) is typically in the region of….
8-10 degrees
Stefanyshyn et al. (2001) reported that uninjured runners demonstrated…
Higher amounts of pronation than injured runners
A hammer thrower achieves an angular velocity of 229deg/s just prior to release.
Calculate the linear velocity of the hammer assuming the cable is 1m in length + hammer throwers arms are 0.75m in length to the axis of rotation.
7 m/s
A cricketer bowls w/ a linear velocity of 28m/s.
If the distance from the ball to the axis of rotation is 0.9m, what is the angular velocity at release?
31.1 rad/s
