Work interaction, power integral calculation

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SUMMARY

The discussion focuses on calculating work and power for a person weighing 800 lbf climbing a flight of stairs with a vertical distance of 300 ft. The work is determined using the formula W = F * D, where F is the force (weight) and D is the distance. The power required for the climb is calculated by dividing the work by the time taken, using the formula Power = F * V, where V is the velocity derived from the distance and time. The key takeaway is that work remains constant regardless of the time taken, while power varies with the duration of the climb.

PREREQUISITES
  • Understanding of basic physics concepts, specifically work and power
  • Familiarity with the formulas W = F * D and Power = F * V
  • Knowledge of English unit conversions, particularly weight (lbf) to mass (slugs)
  • Basic grasp of Newton's laws of motion
NEXT STEPS
  • Calculate work and power for different weights and distances using W = F * D and Power = F * V
  • Explore the implications of varying time durations on power calculations
  • Study the relationship between force, mass, and acceleration in the context of climbing
  • Investigate real-world applications of work and power in physical activities
USEFUL FOR

This discussion is beneficial for physics students, educators, and anyone interested in understanding the principles of work and power in mechanical systems.

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Homework Statement


A person weighing 800 lbf climbs a flight of stairs that extends a vertical distance of 300ft. Calculate the work and power required for this process if it requires 3 min, 5 min, and 10 min.


Homework Equations


W=integral(Fds)
Power=FV


The Attempt at a Solution


I suppose from the wording of this problem the force would be F = ma. 800 lbf is the weight, so w=mg/gc (gc for english units) you would get mass, thus plug in with acceleration and get force. Since the work forumula only requires the distance and force, work would be the same regardless of how long it takes right? The difference would be the power, and since the distance is 300 ft and times are given, you would get velocity and thus multiply with force (using equation 2) to get the power? Am I doing this problem correctly? I'm a bit confused because the wording is not very descriptive and I start thinking about how many steps there are, the horizontal length of the staircase..etc. but I think in this case you have to just use the numbers they give you. Thanks.
 
Physics news on Phys.org
Person weighs 800 pounds? Big person.

Work = F * D

The force is simply the weight. Distance is the measurement of how far the force acted.

Work does not depend on velocity.


Power is the rate at which work is done. So if you want to get work done faster, what does that tell you about power?

Newton's Second Law is not used to solve this problem.
 

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