Moving about question (1 Viewer)

nazfiz

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A 50Kg man climbs to the top of a bungee jump platform, exactly 100m above a river. he is securely attached to a rubber bungee rope. The man leaps off the platform. He free falls for 50m and then the bungee rope stretches a further 50m, stopping the man safely, just above the river.

a) calculate the speed of the person after their first 50m free fall.
b) Calculate the average deceleration of the person between this 50m point and when they stop at 100m.


Thanks in advance! Any help will be repped.
 

RivalryofTroll

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A 50Kg man climbs to the top of a bungee jump platform, exactly 100m above a river. he is securely attached to a rubber bungee rope. The man leaps off the platform. He free falls for 50m and then the bungee rope stretches a further 50m, stopping the man safely, just above the river.

a) calculate the speed of the person after their first 50m free fall.
b) Calculate the average deceleration of the person between this 50m point and when they stop at 100m.


Thanks in advance! Any help will be repped.
awkward moment when rep is gone.
 

bleakarcher

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lol rep system is gone m8

a) v^2=u^2+2as
Since u=0, a=g, => v^2=2gs
When s=50. => v^2=100g=1000 taking g=10 m/s^2
Hence, the velocity of the man at the end of free fall is roughly sqrt(1000) m/s
b) v^2=u^2+2as (Note that I will changing the reference point to where the rope reaches natural length)
=> a=[v^2-u^2]/2s
Since u=sqrt(1000), => a=[v^2-1000]/2s
When s=50, v=0, => a=-1000/(2*50)=-10 m/s^2
Hence, the average deceleration between these two points is 10 m/s^2.
 

nazfiz

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lol rep system is gone m8

a) v^2=u^2+2as
Since u=0, a=g, => v^2=2gs
When s=50. => v^2=100g=1000 taking g=10 m/s^2
Hence, the velocity of the man at the end of free fall is roughly sqrt(1000) m/s
b) v^2=u^2+2as (Note that I will changing the reference point to where the rope reaches natural length)
=> a=[v^2-u^2]/2s
Since u=sqrt(1000), => a=[v^2-1000]/2s
When s=50, v=0, => a=-1000/(2*50)=-10 m/s^2
Hence, the average deceleration between these two points is 10 m/s^2.
thanks! LOL sorry didn't know about the rep system, haven't been on BoS in a while.
 

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