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file:///Users/apple/Desktop/1.pic.jpgAstudentwhojustgot10/10onaPhysicsmidtermdecidestotrybungeejumpingasareward.Heattachesanelasticbungeecordtohisanklesandhappilyjumpsoffatallbridgeacrossariver.Heendsupbarelytou
题目详情
file:///Users/apple/Desktop/1.pic.jpg
A student who just got 10/10 on a Physics midterm decides to try bungee jumping as a reward.He attaches an elastic bungee cord to his ankles and happily jumps off a tall bridge across a river.He ends up barely touching the water before the cord jerks him back up.The bungee cord has an unstretched length of ℓ=5.5 m and a spring constant of k=17 N/m; the distance from the bridge to the water surface is L=55 m.
Eventually you will be asked to find the mass,m,of the student.
15.[1pt]
What is the potential energy stored in the bungee cord just after the student steps off the bridge?
16.[1pt]
What is the mass,m,of the student?
17.[1pt]
What is the speed,v,of the student when the bungee cord just begins to stretch?
18.[1pt]
Which of the following expressions has the dimensions of mass?E.g.,if expressions A and D have the correct dimensions,enter AD; if none are correct,enter N.You only have 4 tries!
k·L/g
k·g
k(L−ℓ)2/L
k/(gv)
k·g/L
k·L/v
19.[1pt]
At what height above the river does the student eventually come to rest after bobbing up and down a few times?
A student who just got 10/10 on a Physics midterm decides to try bungee jumping as a reward.He attaches an elastic bungee cord to his ankles and happily jumps off a tall bridge across a river.He ends up barely touching the water before the cord jerks him back up.The bungee cord has an unstretched length of ℓ=5.5 m and a spring constant of k=17 N/m; the distance from the bridge to the water surface is L=55 m.
Eventually you will be asked to find the mass,m,of the student.
15.[1pt]
What is the potential energy stored in the bungee cord just after the student steps off the bridge?
16.[1pt]
What is the mass,m,of the student?
17.[1pt]
What is the speed,v,of the student when the bungee cord just begins to stretch?
18.[1pt]
Which of the following expressions has the dimensions of mass?E.g.,if expressions A and D have the correct dimensions,enter AD; if none are correct,enter N.You only have 4 tries!
k·L/g
k·g
k(L−ℓ)2/L
k/(gv)
k·g/L
k·L/v
19.[1pt]
At what height above the river does the student eventually come to rest after bobbing up and down a few times?
▼优质解答
答案和解析
答案
15 0
16 m=38.64kg
17 v=10.38m/s
18 选A
19 h=27.23m
15 0
16 m=38.64kg
17 v=10.38m/s
18 选A
19 h=27.23m
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