Particles of mass 10^-2kg is fixed to the tip of a fan blade which rotates...

Particles of mass 10^-2kg is fixed to the tip of a fan blade which rotates with angular velocity of 100rad-1. If the radius of the blade is 0.2m, the centripetal force is

  • A. 2 N
  • B. 20 N
  • C. 200 N
  • D. 400 N
Correct Answer: Option B
Explanation

F = \(\frac{mv ^2}{r}\)

= \(mω^2r\)

(Since V = ωr)

F = 10\(^{-2}\) x 100\(^2\) x 0.2

F =20 N


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Contributions (123)

style rib
4 years ago
F=?,V=100,R=0.2, M=0.01

since F=MWV making W d sof since is not given

W=V/R substituting it in the equation abve

F=Mv²/R inserting the values

F=0.01×10000/0.2

F=100/0.2

F=1000/2

F=500

no answer check this pals
kutuku
6 years ago
D ans is 'c' bcos m=10^-2 w=100rad^-1 r=0.1m using f=mv^2/r

Recall dat v=wr . V=100*0.2 den v=20N put 'v' into f=mv^2/r f=0.1*400/0.2

F=200N

NB dat 10^-2 =0.1 nd nt 0.01
JOSEPH
8 months ago
given that m(v*v)/r
m:10 kg~0.01
v:100 rad
r:0.2m
0.01*100*100/0.2=500N
As my own answer
Enkaay
6 years ago
@kutuku...10^-2 cant b 0.1,buh itz 0.01
Queeneth55
3 years ago
which formular is this guys???
fatimohosun
5 years ago
20N is d answer
omonigho
5 months ago
Since v=wr
F=m(wr)^2/r
F=mw^2r
Lawal Olanrewaju
6 years ago
Following the equation below>F=MV^2/R.where f is centripental force,m is mass of body,v is linear velocity.V=wr.now let substitute v for wr in the initial equation>F=mw^2r^2/r now this then gives f=mw^2r.wow!Now lets input our values.f=1/100*10000*0.2=20N. Pls i can't shout.
ADAADA 777
3 years ago
See, the whole confusion here is in converting 10^-2, nd I think it is 0.10, not 0.01. That's what varies the answer; if u use 0.01 u get 20N; if it's 0.10 u get 200N. It should be 200N.
  • Olanrewaju Abiola: 10^2 = 0.01 because taking the decimal forward to form 10 will be twice.
    F=mv^2/r..... V=wr, w=100, then v=100x0.2=20. m=0.01, r=0.2
    F=0.01x400/0.2 =20N.
    Like 1    Dislike 0   7 months ago
Esiayo
2 years ago
I'll go for B dose saying C shud rethink and resolve. Tanx
ikechukwu
6 months ago
F=mv^2÷r
F=10^-2×100^2÷0.2
F=100÷0.2
F=500N
Adaraloye25
5 years ago
v is not given so we get to find it by using:v=rw,then we can now bring our centripetal force formular,f=mv^2/r,0.01*20^2/0.2,it gives 20N.
zetaboy
4 years ago
GUYS ...REMEMBER DAT 10#-2(D # MEANS EXPONENTIAL). IS D SAME AS 1*10#-2 MEANING 0.01
spunky great
3 years ago
d kret and is 20n bcos mw^2r=10^-2*100^2*0.2=20.
W. Pastore
6 years ago
guys please explain better am confused
  • awe fezighe daniel: f=M(Vsquare )/r but we don't know the value of v so we recall that v =wr from angular velocity formula. then our v = 100×0•2=20m/s. we then substitute the value of v into f=M(Vsquare )/r =0•01×20×20/0•2 =4/0•2= 20N remember that our m=0•01, r=0•2 and Vsquare =20×20=400
    Like 0    Dislike 0   4 years ago

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