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Quick Motion Question (1 Viewer)

sanzach

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A falling body experiences both the gravitational acceleration g and air resistance that
is proportional to its velocity. Thus a typical equation of motion is x(double dot) = −10 − 2v m/s^-2 .
Suppose that the body is dropped from the origin.

By writing x(double dot) = dv/dt and taking reciprocals, find t as a function of v, and hence find v
as a function of t. Then find x as a function of t.

I understand what it's asking but don't know where my error is in the integration.
 

kawaiipotato

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A falling body experiences both the gravitational acceleration g and air resistance that
is proportional to its velocity. Thus a typical equation of motion is x(double dot) = −10 − 2v m/s^-2 .
Suppose that the body is dropped from the origin.

By writing x(double dot) = dv/dt and taking reciprocals, find t as a function of v, and hence find v
as a function of t. Then find x as a function of t.

I understand what it's asking but don't know where my error is in the integration.






























 

braintic

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The velocity starts at zero and heads towards -5 ..... I thought you said this question was about quick motion ? .......
 

sanzach

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Thanks for this, didnt correctly find the constant of integration.
 

sanzach

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Sorry dude, i think you misinterpreted the title there... I meant it as in a speedy question, not referring to anything other than basic motion.
 

braintic

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Sorry dude, i think you misinterpreted the title there... I meant it as in a speedy question, not referring to anything other than basic motion.
And ..... I think you didn't notice that my tongue was firmly planted in my cheek.
 

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