How to calculate average power in this case?

  • Thread starter Thread starter NafeesAhmed
  • Start date Start date
  • Tags Tags
    Average Power
Click For Summary

Homework Help Overview

The problem involves calculating the average power consumed by a runner who rises a certain height over a specified time. The subject area relates to mechanics and energy, specifically focusing on work and power concepts.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants discuss the formula for power and the relationship between work and force. Questions arise about the correct interpretation of work and the need for additional information, such as the runner's mass, to proceed with calculations.

Discussion Status

The discussion is ongoing, with participants exploring the necessary components to calculate average power. There is a recognition of the need for mass to determine work done, and some participants are questioning the assumptions made in the initial attempt.

Contextual Notes

There is a noted absence of information regarding the mass of the runner, which is critical for calculating work done. Participants are also reflecting on the definitions and relationships between force, work, and power.

NafeesAhmed
Messages
6
Reaction score
0

Homework Statement


A runner is rises up by 4.5 meters in 3.5 seconds, what average power must be consumed?


Homework Equations


P=w/t
w=F.d


The Attempt at a Solution


p=4.5/3.5= 1.28 watt
 
Physics news on Phys.org
Average power is work done divided by time taken, as you've correctly written: P = W/t.

But you have substituted in a distance for W; this is incorrect, W is the work done and is measured in joules.

What has the runner done work against? What type of energy has changed?
 
thats exactly what i wanted to ask, as we know w=f.d here we can use d=4.5m but what about F?
 
What force is acting on the runner (there's only one :) )?

I've just realized there's no mass - you can't get a numerical answer without knowing the mass of the runner. Did you not get given a value for the mass?
 

Similar threads

Calculating Average Power and Energy Consumption for a Heater
  • · Replies 10 ·
Replies
10
Views
2K
How many crates can you load in a minute with different average power outputs?
  • · Replies 1 ·
Replies
1
Views
2K
Worksheet Problem about Power (average power of a car accelerating up a hill)
  • · Replies 2 ·
Replies
2
Views
2K
Avg Power in a Rotational Energy/Work Problem
  • · Replies 6 ·
Replies
6
Views
2K
Power calculations of AC signal
  • · Replies 1 ·
Replies
1
Views
2K
Instantaneous Power calculation
  • · Replies 5 ·
Replies
5
Views
8K
Calculate Avg Power Output for 75kg Person Walking 100ft in 3min
  • · Replies 9 ·
Replies
9
Views
2K
Runner's Average Velocity: 0.014 m/s
  • · Replies 17 ·
Replies
17
Views
2K
How Do You Calculate Power from Torque and Angular Velocity?
  • · Replies 3 ·
Replies
3
Views
2K
What is the Power Output of Gravity?
  • · Replies 6 ·
Replies
6
Views
2K