Differential free falling bodies

darthxepher
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(i) how you solved this problem,

An object of mass 10 kg is dropped from a great height. (a) If the object is subjected to air resistance equivalent to 10 times the instantaneous velocity, find the velocity. (b) How far does the object drop after 5 sec?

(ii) what you got as a solution,

Don't know how to start. But i know you use differential equations.

(iii) why you think that is wrong.
 
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try writing what the force or acceleration is at any given instant...
 
Would it be 10(dv/dt)=98-10v?
 
looks ok to me, now mass drops out of the equation, as it mulitplies every term..

now you can look at solving, probably a good place for separation of variables - what do you think?
 

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