Flag Mechanics> please help...
question mark

1790_22321_figure.jpg

Q.A particle moves from rest at A on the surface of a smooth cylinder of radius r as shown.At B it leaves the cylinder.The equation relating alpha and beta is

a.)3sin(alpha)=2cos(beta)

b.)2sin(alpha)=3cos(beta)

c.) 3sin(beta)=2cos(alpha)

d.)2sin(beta)=3cos(alpha)

Raj Deol , 14 Years ago
Grade 11
anser 1 Answers
vikas askiitian expert

Last Activity: 14 Years ago

let the horizonta lsurface of sphere is at zero potential....radius of sphere os R...

at point A ,

     KE is 0 ,PE =mgRcos(alpha)

at point B

 KE=mv2 /2 , PE=mgRsin(beta)

applying conservation of energy

 total energy initial = total energy final

 mv2 /2 = mgR{cos(alpha)- sin(beta)}................1

on resolving weight in two components will give one in direction opposite to normal reaction at point B...

so we can say that centripital force is provided by wsin(beta) only because normal reaction is 0 at this point as the body loses contact....

        wsin(beta)=mgsin(beta)=mv2 /R...............2

 on solving 1 and 2 we get

     3sin(beta)=2cos(alpha)

hence option c is correct....

 

 

 

star
LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

tv

Full Live Access

material

Study Material

removal

Live Doubts Solving

assignment

Daily Class Assignments