physics
mechanics
Easy

Question

A smooth uniform rod of length L and mass M has two identical beads (1 and 2) of negligible size, each of mass m, which can slide freely along the rod. Initially the two beads are at the  centre of the rod and the system is rotating with angular velocity omega subscript a about an axis perpendicular to the rod and is passing through its midpoint. There are no external forces when the beads reach the ends of the rod, the angular velocity of the system is

  1. omega subscript 0
  2. fraction numerator M omega subscript 0 over denominator M plus 6 m end fraction
  3. fraction numerator M omega subscript 0 over denominator M plus 12 m end fraction
  4. fraction numerator M omega subscript 0 over denominator m end fraction

The correct answer is: fraction numerator M omega subscript 0 over denominator M plus 6 m end fraction


    From the conservation of angular momentum
    table attributes columnalign right left right left right left right left right left right left columnspacing 0em 2em 0em 2em 0em 2em 0em 2em 0em 2em 0em rowspacing 3 pt end attributes row cell fraction numerator M L squared over denominator 12 end fraction omega subscript 0 end cell cell equals left square bracket fraction numerator M L squared over denominator 12 end fraction plus 2 m left parenthesis L over 2 right parenthesis squared right square bracket omega end cell row omega cell equals left parenthesis fraction numerator M over denominator M plus 6 m end fraction right parenthesis omega subscript 0 end cell end table

    Related Questions to study

    Mechanics
    Physics

    A solid cylinder of mass M and radius R rotates about its axis with angular speed ω. Its rotational kinetic energy is

    A solid cylinder of mass M and radius R rotates about its axis with angular speed ω. Its rotational kinetic energy is

    PhysicsMechanics
    Mechanics
    Physics

    A wheel of moment of inertia 2.0 cross times 10 cubed kgm squared is rotating at uniform angular speed of 4 rads to the power of negative 1 end exponent. What is the torque required to stop it in one second.

    A wheel of moment of inertia 2.0 cross times 10 cubed kgm squared is rotating at uniform angular speed of 4 rads to the power of negative 1 end exponent. What is the torque required to stop it in one second.

    PhysicsMechanics
    Mechanics
    Physics

    Let  be a force acting on a particle having position vector  . Let   be the torque of this force about the origin, then-

    Let  be a force acting on a particle having position vector  . Let   be the torque of this force about the origin, then-

    PhysicsMechanics
    parallel
    Mechanics
    Physics

    The three similar torque (t) are acting at an angle of 120º with each other. The resultant torque will be-

    The three similar torque (t) are acting at an angle of 120º with each other. The resultant torque will be-

    PhysicsMechanics
    Mechanics
    Physics

    A force of left parenthesis 2 i with hat on top minus 4 j with hat on top plus 2 k with hat on top right parenthesis  Newton acts at a point   left parenthesis 3 i with hat on top plus 2 j with hat on top minus 4 k with hat on top right parenthesis metre from the origin. The magnitude of torque is -

    A force of left parenthesis 2 i with hat on top minus 4 j with hat on top plus 2 k with hat on top right parenthesis  Newton acts at a point   left parenthesis 3 i with hat on top plus 2 j with hat on top minus 4 k with hat on top right parenthesis metre from the origin. The magnitude of torque is -

    PhysicsMechanics
    Mechanics
    Physics

    A disc is rotating with an angular velocity omega0. A constant retarding torque is applied on it to stop the disc. The angular velocity becomes (omega0/2) after n rotations. How many more rotations will it make before coming to rest?

    A disc is rotating with an angular velocity omega0. A constant retarding torque is applied on it to stop the disc. The angular velocity becomes (omega0/2) after n rotations. How many more rotations will it make before coming to rest?

    PhysicsMechanics
    parallel
    Mechanics
    Physics

    A beam of length l lies on the +x axis with its left end on the origin. A cable pulls the beam in  y-direction with a force straight F equals straight F subscript 0 left parenthesis 1 minus straight x over ell right parenthesis.If the axis is fixed at x = 0 then find the torque

    A beam of length l lies on the +x axis with its left end on the origin. A cable pulls the beam in  y-direction with a force straight F equals straight F subscript 0 left parenthesis 1 minus straight x over ell right parenthesis.If the axis is fixed at x = 0 then find the torque

    PhysicsMechanics
    Mechanics
    Physics

    An equilateral triangle ABC has its centre at O as shown in figure. Three forces 10 N, 5N and F are acting along the sides AB, BC and AC. Magnitude of F so that the net torque about ‘O’ is zero is

    An equilateral triangle ABC has its centre at O as shown in figure. Three forces 10 N, 5N and F are acting along the sides AB, BC and AC. Magnitude of F so that the net torque about ‘O’ is zero is

    PhysicsMechanics
    Mechanics
    Physics

    W h e n space a space t o r q u e space a c t i n g space u p o n space a space s y s t e m space i s space z e r o comma space w h i c h space o f space t h e space f o l l o w i n g space w i l l space b e space c o n s tan t ?

    W h e n space a space t o r q u e space a c t i n g space u p o n space a space s y s t e m space i s space z e r o comma space w h i c h space o f space t h e space f o l l o w i n g space w i l l space b e space c o n s tan t ?

    PhysicsMechanics
    parallel
    Mechanics
    Physics

    text  A couple produces  end text

    text  A couple produces  end text

    PhysicsMechanics
    Mechanics
    Physics

    T w o space p a r t i c l e s space A space a n d space B space a r e space s i t u a t e d space a t space a space d i s tan c e space d equals 2 space m space a p a r t. space P a r t i c l e space A space h a s space a space
v e l o c i t y space o f space 10 space m space divided by space s space a t space a n space a n g l e space o f space 60 to the power of 0 space a n d space p a r t i c l e space B space h a s space a space v e l o c i t y space v space a t space a n space a n g l e
30 to the power of 0 space a s space s h o w n space i n space f i g u r e. space T h e space d i s tan c e space d space b e t w e e n space A space a n d space B space i s space c o n s tan t. space T h e space a n g u l a r
space v e l o c i t y space o f space B space w i t h space r e s p e c t space t o space A space i s colon

    T w o space p a r t i c l e s space A space a n d space B space a r e space s i t u a t e d space a t space a space d i s tan c e space d equals 2 space m space a p a r t. space P a r t i c l e space A space h a s space a space
v e l o c i t y space o f space 10 space m space divided by space s space a t space a n space a n g l e space o f space 60 to the power of 0 space a n d space p a r t i c l e space B space h a s space a space v e l o c i t y space v space a t space a n space a n g l e
30 to the power of 0 space a s space s h o w n space i n space f i g u r e. space T h e space d i s tan c e space d space b e t w e e n space A space a n d space B space i s space c o n s tan t. space T h e space a n g u l a r
space v e l o c i t y space o f space B space w i t h space r e s p e c t space t o space A space i s colon

    PhysicsMechanics
    Mechanics
    Physics

    A space h o o p space r o l l s space o n space a space h o r i z o n t a l space g r o u n d space w i t h o u t space s l i p p i n g space w i t h space l i n e a r space s p e e d space v. space S p e e d space o f space a space
p a r t i c l e space P space o n space t h e space c i r c u m f e r e n c e space o f space t h e space h o o p space a t space a n g l e space theta space i s colon

    A space h o o p space r o l l s space o n space a space h o r i z o n t a l space g r o u n d space w i t h o u t space s l i p p i n g space w i t h space l i n e a r space s p e e d space v. space S p e e d space o f space a space
p a r t i c l e space P space o n space t h e space c i r c u m f e r e n c e space o f space t h e space h o o p space a t space a n g l e space theta space i s colon

    PhysicsMechanics
    parallel
    Mechanics
    Physics

    A space d i s c space o f space r a d i u s space r space r o l l s space o n space a space h o r i z o n t a l space g r o u n d space w i t h space l i n e a r space a c c e l e r a t i o n space a space a n d space a n g u l a r space
a c c e l e r a t i o n space alpha space a s space s h o w n space i n space f i g u r e. space T h e space m a g n i t u d e space o f space a c c e l e r a t i o n space o f space p o i n t space P space
s h o w n space i n space f i g u r e space a t space a n space i n s tan t space w h e n space i t s space l i n e a r space v e l o c i t y space i s space v space a n d space a n g u l a r space v e l o c i t y space i s
omega space w i l l space b e colon

    A space d i s c space o f space r a d i u s space r space r o l l s space o n space a space h o r i z o n t a l space g r o u n d space w i t h space l i n e a r space a c c e l e r a t i o n space a space a n d space a n g u l a r space
a c c e l e r a t i o n space alpha space a s space s h o w n space i n space f i g u r e. space T h e space m a g n i t u d e space o f space a c c e l e r a t i o n space o f space p o i n t space P space
s h o w n space i n space f i g u r e space a t space a n space i n s tan t space w h e n space i t s space l i n e a r space v e l o c i t y space i s space v space a n d space a n g u l a r space v e l o c i t y space i s
omega space w i l l space b e colon

    PhysicsMechanics
    Mechanics
    Physics

    I n space f i g u r e comma space w h e e l space A space o f space r a d i u s space r subscript A equals 10 space c m space i s space c o u p l e d space b y space b e l t space B space t o space w h e e l space C space o f space
r a d i u s space r subscript C equals space 25 space c m. space T h e space a n g u l a r space s p e e d space o f space w h e e l space A space i s space i n c r e a s e d space f r o m space r e s t space a t
a space c o n s tan t space r a t e space o f space 1.6 space r a d space divided by space s squared. space F i n d space t h e space t i m e space n e e d e d space f o r space w h e e l space C space t o space r e a c h space
a n space a n g u l a r space s p e e d space o f space 12.8 space r a d space divided by space s comma space a s s u m i n g space t h e space b e l t space d o e s space n o t space s l i p.

    I n space f i g u r e comma space w h e e l space A space o f space r a d i u s space r subscript A equals 10 space c m space i s space c o u p l e d space b y space b e l t space B space t o space w h e e l space C space o f space
r a d i u s space r subscript C equals space 25 space c m. space T h e space a n g u l a r space s p e e d space o f space w h e e l space A space i s space i n c r e a s e d space f r o m space r e s t space a t
a space c o n s tan t space r a t e space o f space 1.6 space r a d space divided by space s squared. space F i n d space t h e space t i m e space n e e d e d space f o r space w h e e l space C space t o space r e a c h space
a n space a n g u l a r space s p e e d space o f space 12.8 space r a d space divided by space s comma space a s s u m i n g space t h e space b e l t space d o e s space n o t space s l i p.

    PhysicsMechanics
    Mechanics
    Physics

    A space d i v e r space m a k e s space 2.5 space r e v o l u t i o n s space o n space t h e space w a y space f r o m space a space 10 minus space m space minus h i g h space p l a t f o r m space t o space t h e space
w a t e r. space A s s u m i n g space z e r o space i n i t i a l space v e r t i c a l space v e l o c i t y comma space t h e space a v e r a g e space a n g u l a r space v e l o c i t y space
d u r i n g space t h e space d i v e space i s

    A space d i v e r space m a k e s space 2.5 space r e v o l u t i o n s space o n space t h e space w a y space f r o m space a space 10 minus space m space minus h i g h space p l a t f o r m space t o space t h e space
w a t e r. space A s s u m i n g space z e r o space i n i t i a l space v e r t i c a l space v e l o c i t y comma space t h e space a v e r a g e space a n g u l a r space v e l o c i t y space
d u r i n g space t h e space d i v e space i s

    PhysicsMechanics
    parallel

    card img

    With Turito Academy.

    card img

    With Turito Foundation.

    card img

    Get an Expert Advice From Turito.

    Turito Academy

    card img

    With Turito Academy.

    Test Prep

    card img

    With Turito Foundation.