HOMOKINETICS
II
PRACTICE
PROBLEMS II
1. The knee extension of a swimmer who is performing the flutter kick is 1 rad/s at one point and .03 seconds later the angular velocity is 1.1 rad/s. Calculate the angular acceleration between the two points.
2.
A
tennis racket swung with an angular velocity of 12 rad/s strikes a motionless
ball with a linear velocity of 6 m/s.
What is the radius of rotation?
3.
A
tennis ball leaves a racket during the execution of a perfect horizontal ground
stroke at a 20 degree angle, with a velocity of 22 m/s. If the ball is in the air for 0.7 seconds,
how high and far does the ball travel?
4.
A
volleyball player underhand passes a ball with an initial velocity of 6
m/s. The ball is in the air for 2.5
seconds. How far does the ball go?
5.
A
gymnast is on the horizontal bar. If
his angular velocity is 250 deg/s at the instant he passes through the
horizontal on his downward swing and 400 deg/s as he passes below the bar 0.3
sec later. What is his angular
acceleration?
6.
A
kicker’s extended leg is swung for 0.4 sec in a counterclockwise direction
while accelerating 200 deg/s2.
What is the angular velocity of the leg at the instant of contact with
the ball?
7.
A
famous SIUE cliff diver is performing an unforgettable dive into Cougar
Lake. The diver performs a back, 1 3/4
somersault dive from the 5 m cliff. If
the diver enters the water 1.4 sec later, what angular distance and
displacement did the diver experience as a result of the somersaulting motion?