Question

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4.59答案為什麼是a

mass, are 「 PASSAGE PROBLEMS
了                       R/S BODY. Dancers experience

jjmps they make. Tor example

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when a dancef ]an
head by 過e neck
cause 負e head to $
9g.4% of atypical personsm
Janding after a Vertical Jump $

4.0 m/s to restinatime of 0.20 S.
4,57 What 1$ the magnitude Of the average force that her neck

exerts on her head during the ]anding? (3) ON; (b) 6O N; (c) 120 N:

must exceed the
jow down and come to Tes- The head is about

as8. Video analysis ot a 65-kg dancer
hows that her head decelerates from

hthe force her neck exerts on her head during

the ]anding, the force her head exerts On her neck 1S (3) the Sames:

(b) greater; (co) smaller: (d) greater during the first half ot the land-
uring the second halt of the ]anding.

4.,58 Compared Wit

9 and smaller d
4,59 While the dancer 1S in the air and holding a fixed bose

what is the magnitude of the force her neck exertS On her heady
(3 ON; (b) 6O N; (o]) 120 N; (0) 180 N.
4.60 The forces ona dancer can be measSsured directly When a
dancer performs aJump On a force plate that measSures the 10rfce
betWween her feet and the ground. A graph Of force verSus time
es a Vertical jump performed on aforce plate is Shown lt
es at 1S happening at 0.4 $? The dancer is (3) bendlng
0 1S acceleratling downward; (b) pushtung
er legs and is almost ready to leave the ground

(o in the air and at the to
have just touched the 一 her jump; (d) landing and her feel

Figure P4.60

laree toOTCeS                         對
4 adancer ]ands afterf a Vertical ]uimp, the force eXerted on the

head by the neck mus$t exceed the head $ Welg 1t by enough t0
cause the head to slow dowh and come to TeSt. 』 he head 1S about
9,496 of atypical persOn$ masSS. Video analyS1$S Of a 6?-Kg dancer
]anding after a Vertical jump shows that her head decelerates from
4.0 m/s to rest in atime Of 0.20 S.

4.57 What is the magnitude of the average force that her heck

eXertS on her head durling the landing7 (3) ON;(b) 6O N: (c 120N)
(d 180 N.

RSs BODY Dancers experience
sthey make. For example,
]arge forces 3SS0CI4            iceal jump, the force eXerted on the

head by the neck must exceed the head 5 welght by enough to
ea

St. The head 1S about
cause the head tosow 和 0 Of a 65-Keg dahncer
g,4% Of atypical DersOn $ ma55. Video ana!  還 汪 同
landing after a vertical jump Shows that heT
4.0 m/s to restin atime 0f U.z0 5.

和.57 What is the magnitude of the average force that her heck
eXerts On her head during the landing? (3 0N; (b) 6O0 N: (c) 120 N;
(0 180 N.
4,98 Gompared with the force her neck exerts on her head durlng
te landing, the force her head exerts on her neck jx (a) the Same;
0) greater; (c) smaller; (d) greater during the first half of the ]and-

0    ‧                     同
 宙 and Smaller during the Second half of the landing

 

and holding a fixed DoOS6,
【HecK exerts on her head?

Answer 1

訪客

內力