Solve
Study
Textbooks
Guides
Use app
Login
>>
Class 11
>>
Physics
>>
Systems of Particles and Rotational Motion
>>
Medium Questions
Systems Of Particles And Rotational Motion
Physics
6914 Views
Easy Qs
Med Qs
Hard Qs
>
A constant torque acting on a uniform circular wheel changes its angular momentum from
$L$
to
$4L$
in
$4$
seconds. The torque acting on it is:
A
$4L$
B
$12L$
C
$43 L$
D
$34 L$
Medium
View solution
>
A particle of mass
$m$
moves uniformly with a speed
$v$
along a circle of radius
$r$
. A and B are two points on the circle, such that the arc
$AB$
subtends an angle
$θ$
at the center of the circle. The magnitude of change in momentum as the particle moves from
$A$
to
$B$
is given by:
A
$2mvsin(2θ )$
B
$2mvcos(2θ )$
C
$zero$
D
$2mvtan(2θ )$
Medium
View solution
>
The kinetic energy of a moving body is given by
$K=2v_{2}$
,
$K$
being in joules and
$v$
in m/s. Its momentum when traveling with a velocity of
$2ms_{−1}$
will be :
A
$16kgms_{−1}$
B
$4kgms_{−1}$
C
$8kgms_{−1}$
D
$2kgms_{−1}$
Medium
View solution
>
A torque of
$0.5Nm$
is required to drive a screw into a wooden frame with the help of a screw driver. If one of the two forces of couple produced by screw driver is
$50N$
, the width of the screw driver is:
A
$0.5cm$
B
$0.75cm$
C
$1cm$
D
$1.5cm$
Medium
View solution
>
The position of axis of rotation of a body is changed so that its moment of inertia decreases by 36%. Find the % change in its radius of gyration.
A
It decreases by 18%
B
It increases by 18%
C
It decreases by 20%
D
It increases by 20%
Medium
View solution
>
The radius of gyration of a rotating metallic disc is independent of which of the following physical quantity.
A
Position of axis of rotation
B
Mass of disc
C
Radius of disc
D
Centre of mass of disc
Medium
View solution
>
A wheel of radius
$R$
is free to rotate about its natural axis and
$I$
is its moment of inertia. If a tangential force
$F$
is applied on the wheel along its rim, then angular acceleration of wheel is:
A
$IFR$
B
$IFR $
C
$RIF $
D
$FIR $
Medium
View solution
>
A flywheel making
$120$
r.p.m is acted upon by a retarding torque producing angular retardation of
$πrad/s_{2}$
. Time taken by it to come to rest is:
A
$1$
s
B
$2$
s
C
$3$
s
D
$4$
s
Medium
View solution
>
A brass disc is rotating about its axis. If temperature of the disc is increased then its:
A
radius of gyration increases, but moment of inertia remains the same
B
moment of inertia increases but radius of gyration remains the same
C
radius of gyration and moment of inertia both remain the same
D
radius of gyration and moment of inertia both increases
Medium
View solution
>
Four particles each of mass
$m$
are placed at the corners of a square of side length
$l$
. The radius of gyration of the system about an axis perpendicular to the square and passing through its center is:
A
$2 l $
B
$2l $
C
$l$
D
$(2 )l$
Medium
View solution
>