
#1
Mar205, 06:36 PM

P: 143

A particle of mass [tex]M[/tex] moves along a straight line with initial speed [tex]v_i[/tex]. A force of magnitude [tex]F[/tex]pushes the particle a distance [tex]D[/tex] along the direction of its motion.
assume that the particle's mass is increased to 3M. B.)By what multiplicative factor [tex]R_k[/tex] does the initial kinetic energy increase, and by what multiplicative factor [tex]R_w[/tex] does the work done by the force increase (with respect to the case when the particle had a mass [tex]M[/tex]) If one of the quantities doubles, for instance, it would increase by a factor of 2. If a quantity stays the same, then the multiplicative factor would be 1. You should enter the two factors separated by a comma. [tex]R_k,R_w = ___________ [/tex] this is what i think: to find [tex]R_k[/tex] i must use this formula: 1/2*m*v^2 to find [tex]R_W[/tex], i must use this formula: W=f*d okay, now to find r_k: 1/2*M*v^2 = 3M (cancel everything and get only 3) now to find r_w: [tex]W = 1/2*M*v_i^2+F*D 1/2*M*v_i^2 = 1/2*3M*v_i^2+F*D 1/2*3M*v_i^2[/tex] < i get 0, is this correct? i'm pretty sure i'm doing it incorrectly, but i dont know how to correct it. can someone help? 



#2
Mar205, 06:42 PM

P: 1,445

what does Rk and Rw correspond? does Rk or Rw ask for the 3M part or the M part??
Please type out the question exactly how you read it. This doesn't make any sense otherwise. 



#3
Mar205, 06:44 PM

P: 143

i copied the whole thing (it's online,so i just copied and pasted). but R_K is kinetic energy multiplicative factor and R_w is tk work multiplicative factor
edit: i just figured it out, thanks anyways 


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