Work energy principle and power

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SUMMARY

The discussion revolves around the application of the work-energy principle to calculate the speed of a girl descending a water slide. Given her mass of 50 kg, initial speed of 2 m/s, and a vertical height of 5 m, the theoretical speed at the bottom without resistance is calculated to be 10.2 m/s. However, accounting for an average resistance force of 40 N, the actual final speed is 8 m/s, leading to a discrepancy in the calculated length of the slide. The correct length, determined using the work-energy principle, is 25 meters.

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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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