Speed on an object given F and Ek....

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Homework Help Overview

The problem involves calculating the speed of an object given its kinetic energy and weight, specifically focusing on the relationship between force, mass, and kinetic energy.

Discussion Character

  • Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to derive the speed using the kinetic energy formula and questions the correctness of their calculations. Some participants engage in light-hearted banter regarding the need for accuracy in taking the square root.

Discussion Status

The discussion includes attempts to verify calculations and clarify the correct application of formulas. There is an acknowledgment of a mistake in the calculation, leading to a revised speed estimate.

Contextual Notes

Participants reference the gravitational force and its role in determining mass, indicating a potential assumption about the local gravitational field strength.

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Homework Statement


The kinetic energy of a 20N object is 5.00 x 10^2 J. What is the speed?

Homework Equations


Ek= 1/2 mv^2
and *i think*
F=mg

The Attempt at a Solution


F=mg
m=F/g
m=20N/9.81 m/s^2
m= 2.038 kg Ek= 1/2 mv^2
v=sq. root 2Ek/m
v=sq. root 2(5.00 x 10^2 J)/2.038 kg
v= 490 m/sIs this correct or do i need Jesus? lol
 
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talknerdy2me said:
Is this correct or do i need Jesus? lol
You don't need Jesus, you need to take the square root, lol2.
 
oh duh! ok so ... 22. 135 m/s?
 
Yup.
 

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