Calculating Work Done by Force on a Block

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Homework Help Overview

The problem involves calculating the work done by a force on a block being pulled across a horizontal surface. The scenario includes a block with a specified mass and velocity, and an applied force at an angle, focusing on the concept of power in relation to work done.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the relationship between work and power, with one attempting to calculate work using kinetic energy equations and another exploring the formula for power in terms of force and velocity.

Discussion Status

The discussion includes attempts to clarify the definitions of work and power, with some participants providing calculations and seeking confirmation on their reasoning. There is a mix of approaches being explored without a clear consensus on the correct method.

Contextual Notes

Participants are working within the constraints of a homework assignment, which may limit the information available for solving the problem. Assumptions about the direction of force and the nature of the motion are also being questioned.

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Homework Statement



A 100 kg block is pulled at a constant speed of 3 m/s across a horizontal floor by an applied foce of 145 N directed 37 degrees above the horizontal. What is the rate at which the force does work on the block? _____ W

Homework Equations


work = force (dot product) displacement
work = .5m * v^2 (final) - .5m *v^2 (initial)


The Attempt at a Solution



i used the second equation and plugged in my mass as 100kg and my final velocity as 3. so i got .5(100)(3^2) = 450 W. That seems like an awful lot to me ?
 
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Its the rate at which force does work.
What is the rate at which work is done known as?
 
Is it power?
 
This is something else I've tried.

Power = work / time = force (dot product) displacement = force * average velocity * cos(37 desgrees). I cam out with 347. 41 W. Am I doing this correctly?
 
Solved. Thanks for jogging my memory!
 

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