MHB Work energy principle and power

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A girl with a mass of 50 kg descends a water slide from a height of 5m, starting with a speed of 2 m/s. Without resistance, her speed at the bottom would be 10.2 m/s, but due to an average resistance of 40N, her actual speed is 8 m/s. The calculated length of the slide based on the work-energy principle is 25m, which aligns with the textbook answer. The discussion highlights the application of the work-energy principle in solving problems involving energy conservation and resistance. Understanding these concepts is crucial for accurately determining speeds and distances in physics problems.
Shah 72
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A girl of mass 50 kg travels down a water slide. She starts at the top with a speed of 2 m/s and descends through a vertical height of 5m.
a) Assuming that there is no resistance, find her speed when she reaches the bottom of the slide
I got the ans 10.2m/ s
b) the girl's actual final speed is 8m/s because there is resistance of average value of 40N. Find the length of the water slide.
I get the ans 37.5
The ans in textbook is 25m
Pls help
 
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Shah 72 said:
A girl of mass 50 kg travels down a water slide. She starts at the top with a speed of 2 m/s and descends through a vertical height of 5m.
a) Assuming that there is no resistance, find her speed when she reaches the bottom of the slide
I got the ans 10.2m/ s
b) the girl's actual final speed is 8m/s because there is resistance of average value of 40N. Find the length of the water slide.
I get the ans 37.5
The ans in textbook is 25m
Pls help
I got the ans of 25m using work energy principle.
Thanks!
 

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