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

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The discussion revolves around calculating the speed of a 20N object with a kinetic energy of 500 J. The user correctly identifies the equations for kinetic energy and force, calculating the mass as approximately 2.038 kg. After an initial miscalculation, they find the speed using the formula v = sqrt(2Ek/m). The final correct speed is determined to be approximately 22.135 m/s. The conversation highlights the importance of careful calculation and verification in physics problems.
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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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