During a running sprint the runner’s foot is on the ground for 0.097 s and the...
During a running sprint the runner’s foot is on the ground for 0.097 s and the person is in the air for 0.118 s. The runner has a mass of 94 kg. His drag area is 0.58 m2 and air density is 1.11 kg/m3. He s running at an average velocity of 10.51 m/s over level ground.
What is the average GRFy (in units of Newtons) during the ground contact phase?
In order to maintain his average velocity, how much average GRFx must he produce during the ground contact phase?
Homework Answers
speed of the runner when he leaves the ground=acceleration due to gravity*(time in which he is in air/2)
=9.81*0.118/2
=0.57879/s
he will touch down on the ground with this speed but in opposite direction.
impulse applied=change in momentum
==>force*time=mass*(final velocity-initial velocity)
==>force*0.097=94*(0.57879-(-0.57879))
==>force=94*0.57879*2/0.097=1121.77 N
then total reaction force from the ground=weight of the runner+ reaction force during the contact
=1121.77+94*9.81=2043.91 N
Add Answer to:
During a running sprint the runner’s foot is on the ground for
0.097 s and the...
A 82 kg person has his center of gravity 1.0 meters above the ground in a...
A 82 kg person has his center of gravity 1.0 meters above the ground in a standing position (height that person comes off the ground during a jump). During a squat jump, he crouches down so that his centre of gravity is 0.3 meters above the ground. As he jumps, he exerts an average force of 1258 Newtons against the ground. You can think of this average exerted force as the average normal force or average ground reaction force being...
Problem 39. 39. A jogger generates an impulse on the ground during the time from initial...
Problem 39.
39. A jogger generates an impulse on the ground during the time from initial contact (heel strike) to foot lift off (toe .Total Measured Vertical Impulse __ Estimated Vertical Impulse Force INI 2000..- 1000 Time [s 0 0.2 0.8 1 Heel Strike Toe Off . The vertical force component for heel-toe running typically has two peaks, the first due to iniial heel (or toe) impact on the ground and the second when the foot supports full body weight....
Data of elite sprinters indicate that faster athletes realize shorter ground contact times compared with slower...
Data of elite sprinters indicate that faster athletes realize shorter ground contact times compared with slower individuals. Furthermore, the importance of the so- called "front side mechanics" for elite sprint performance is frequently em weight su possible negative effects of this body-weight supporting device on sprint running kinematics, which was not clanified in previous studies. Eleven well-trained by researchers and coaches. Recently, it was demonstrated that using a body- ing kite during full-effort sprints in highly trained sprinters leads to...
A 75 kg man running at 2.5 m/s jumps off a roof that is 3 m...
A 75 kg man running at 2.5 m/s jumps off a roof that is 3 m high. As he hits the ground, he tucks into a ball and rolls without slipping to break his fall. Modeling the man as a solid sphere of a radius 0.75 m, assuming no rotational motion before he hits the ground, and ignoring any effects of him tucking into a ball, what is his center of mass velocity on the ground?
A soccer ball is kicked from the ground with an initial speed of 17.6m/s at an...
A soccer ball is kicked from the ground with an initial speed of 17.6m/s at an upward angle of 42.5 degrees. A player 49.4 m away in the direction of the kicks starts running to meet the ball at that instant. What must be his average speed if he is to meet the ball just before it hits the ground? Neglect air resistance.
During one scene in the movie, X-Men: Days of Future Past, Magneto uses his magnetic powers...
During one scene in the movie, X-Men: Days of Future Past, Magneto uses his magnetic powers to drag Mystique across the ground toward him, relying on a bullet which has been lodged in Mystique’s calf to pull her with a magnetic force, as shown below. Assume that Mystique has a mass of 61.2 kg and that the coefficient of kinetic friction between her and the ground is 0.280. With what force should Magneto pull her if the direction of his...
#1 A 69.6 kg runner has a speed of 3.30 m/s at one instant during a...
#1 A 69.6 kg runner has a speed of 3.30 m/s at one instant during a long-distance event. If the runner's kinetic energy at this instant is 378.98J, how much net work (in J) is required to double his speed? 2b. A 52.0-kg projectile is fired at an angle of 30.0° above the horizontal with an initial speed of 130 m/s from the top of a cliff 156 m above level ground, where the ground is taken to be y...
Due ne wed 30A soccer hall is kicked from the ground with an initial speed of...
Due ne wed 30A soccer hall is kicked from the ground with an initial speed of 19.5 mv's at an upward angle of 45.A player 55 m away in the direction of the kick starts running to moet the ball at that in slant. What imust be his average speed if he is to moet the ball just helore it hits the ground? ch4 "15 SSM ILW A particle leaves the origin with an initial vchK- ity . (3.00i) mrs...
please help!! 4. During a football game, a 115-kg ball carrier brea-kg deften he tad loose...
please help!!
4. During a football game, a 115-kg ball carrier brea-kg deften he tad loose and heads north back moves 5-kg ball carri pan at aspeed of 8.50 m/s. A 135-kg defensihen he tackles at an angle of 30.0° south of west with a sp and holds on to him. What is their velocity immi he eir velocity immediately after impact mpact? speed of 7.50 m/s a) 3.98 m/s b) 6.89 m/s c 3.51 m/s d) 7.96 m/s 11.3...
a 60 kg gymnast leaves the ground with angular momentum about his transverse axis of 15...
a 60 kg gymnast leaves the ground with angular momentum about his transverse axis of 15 kg m2/s. His radius of gyration about the transverse axis is 0.7 m at take-off. During his subsequent somersault, he reduces his radius of gyration to 0.4 m. (a) What is the moment of inertia of the gymnast at take-off? During the somersault? (b) What is the angular velocity of the gymnast at take-off? During the somersault? (c) If it takes the gymnast 0.25...
Problem 39.
39. A jogger generates an impulse on the ground during the time from initial contact (heel strike) to foot lift off (toe .Total Measured Vertical Impulse __ Estimated Vertical Impulse Force INI 2000..- 1000 Time [s 0 0.2 0.8 1 Heel Strike Toe Off . The vertical force component for heel-toe running typically has two peaks, the first due to iniial heel (or toe) impact on the ground and the second when the foot supports full body weight....
Data of elite sprinters indicate that faster athletes realize shorter ground contact times compared with slower individuals. Furthermore, the importance of the so- called "front side mechanics" for elite sprint performance is frequently em weight su possible negative effects of this body-weight supporting device on sprint running kinematics, which was not clanified in previous studies. Eleven well-trained by researchers and coaches. Recently, it was demonstrated that using a body- ing kite during full-effort sprints in highly trained sprinters leads to...
Due ne wed 30A soccer hall is kicked from the ground with an initial speed of 19.5 mv's at an upward angle of 45.A player 55 m away in the direction of the kick starts running to moet the ball at that in slant. What imust be his average speed if he is to moet the ball just helore it hits the ground? ch4 "15 SSM ILW A particle leaves the origin with an initial vchK- ity . (3.00i) mrs...
please help!!
4. During a football game, a 115-kg ball carrier brea-kg deften he tad loose and heads north back moves 5-kg ball carri pan at aspeed of 8.50 m/s. A 135-kg defensihen he tackles at an angle of 30.0° south of west with a sp and holds on to him. What is their velocity immi he eir velocity immediately after impact mpact? speed of 7.50 m/s a) 3.98 m/s b) 6.89 m/s c 3.51 m/s d) 7.96 m/s 11.3...
Most questions answered within 3 hours.
-
Where is the error in this code sequence?
String s1 = "Hello";
String s2 = "ello";...
asked 10 months ago -
Financial data for Joel de Paris, Inc., for last year
follow:
Joel de Paris, Inc.
Balance...
asked 10 months ago -
Consider this reaction:
Al2(SO4)3 (aq)+ BaCl3
(aq) Al2Cl6 (aq)- +
3BaSO4(s) . What is the...
asked 10 months ago -
Suppose that Savneet is considering increasing her
recent random sample from 20 car rentals to 40...
asked 10 months ago -
Trucks arrive at an unloading terminal at an average rate of 120
per hour.
Trucks arrive...
asked 10 months ago -
Why are methanol and ethanol completely soluble in water while
octanol is not very little soluble....
asked 10 months ago -
A facilities manager at a university reads in a research report
that the mean amount of...
asked 10 months ago -
When the CuSO4 is rehydrated by adding water to the anhydrous
compound, is this an endothermic...
asked 10 months ago -
A ray of sunlight is passing from diamond into crown glass; the
angle of incidence is...
asked 10 months ago -
A block of mass 0.249 kg is placed on top of a light, vertical
spring of...
asked 10 months ago -
how do the kidneys compensate in the presences of acidosis
a) trigger hyperventilate
b) reserve acid...
asked 10 months ago -
Question 501 pts
The rental rate of capital to the firm increases. Which of the
following...
asked 10 months ago