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Questions (5)
A ball is thrown straight up at 20.0 m/s. How fast is the ball moving after 2.00 s?
4 answers
491 views
what is the van't Hoff factor for MgSo4.7H2O and ZnSo4.7H2O?
1 answer
2,445 views
what percent of the total population believed saying to be true?
0 answers
801 views
differentiate y=e^x/(x)^(1/2).i need the calculation work.[ans: e^x/x^(1/2) - e^x/2x^(3/2)]
1 answer
372 views
what are the advantages and disadvantages of a butcher and a fish monger
0 answers
447 views
Answers (13)
did you ever figure it out?
answers depend on the values we have so, for A F = dp/dt -> dp = Fdt ∫dp = ∫Fdt p_f - p_i = ∫βt²dt p_f - 0 = (β/3)(t_f)^3 - (β/3)(t_i)^3 for b: F - fk = m.a F - fk = m.dv/dt (F - fk)dt = m.dv ∫(F - f_k)dt = ∫m.dv m.vf - m.vi = (β/3)(tf)^3 -
so... no ideas for this problem???
my values were right, just had to write the value of f without the -. Now, anyone has checked the falling ruler???
so, no more suggestions for b and c of initial question? and Mets, check the videos from week 13.
so I risked one chance and got: a) N=f.d/Vs b) dN/dt=f.Vobs/Vs c) f'=f(1-Vobs/Vs) and I thought for d: f'=f.Vs/(Vs-Vwind) but it's not right, I'll assume f' have to be bigger since, Vwind goes from source to observer.. but well, any suggestions?
but, how did you do with D)???
from a we have: N=f.d/Vs for b: N=f.(d+v.t)/Vs dN/dt=f.v/Vs
error, so we'll have: F-ff=m.a -> ff=F-m.a (1) I.alpha=F.r+ff.R (2) alpha=a/R then: a=F.(R+r)/(I/R+m.R) a=positive ff=negative, and for a got green mark, but not for f, should I write ff with "-" or just the value? I got a=16.3 f=-4.6
It might be better to indicate the equation rather than answers, because the data changes. So, we have: F-ff=ma (1) I.alpha=F.R-ff.r (2) and we have two equation ant variables. but alpha is a/R or a/r
have you check your data, because for a got a green mark, so A is ok, but b and c were not. There might be some where m = 3 and beta=1.2
for b: F - f_k = ma F - f_k = mdv/dt (F - f_k)dt = mdv ∫(F - f_k)dt = ∫mdv mv_f - mv_i = (β/3)(t_f)^3 - (f_k)t_f - [(β/3)(t_i)^3 - (f_k)t_i] [Note: v_i = 0 and t_i = 0] mv_f = (β/3)(t_f)^3 - (f_k)t_f v_f ≅ 10.83, but that's not the answer, so any
for a: 41.67
