Famous palaeonotologist/Palaeobotanist of India was:
- P.Maheshwari
- B.P. Pal
- S. R. Kashyap
- B.Sahni
Answer:The correct answer is: B.Sahni
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Related Questions to study
A disc is rolling (without slipping) on a horizontal surface
is its centre and
and
are two points equidistant from
. Let
,
and
be the magnitude of velocities of pints
and
respectively, then


Velocity of any point on the disc,
where
A disc is rolling (without slipping) on a horizontal surface
is its centre and
and
are two points equidistant from
. Let
,
and
be the magnitude of velocities of pints
and
respectively, then


Velocity of any point on the disc,
where
A small object of uniform density roll up a curved surface with an initial velocity
. If reaches up to a maximum height of
with respect to the initial position. The object is

A small object of uniform density roll up a curved surface with an initial velocity
. If reaches up to a maximum height of
with respect to the initial position. The object is

A uniform rod
of length
and mass
is free to rotate about point
. The rod is released from rest in the horizontal position. Given that the moment of inertia of the rod about
is
, the initial angular acceleration of the rod will be

Where
Torque
or
or
or
A uniform rod
of length
and mass
is free to rotate about point
. The rod is released from rest in the horizontal position. Given that the moment of inertia of the rod about
is
, the initial angular acceleration of the rod will be

Where
Torque
or
or
or
If
then descending order of 
is
If
then descending order of 
is
Three rods of the same mass are placed as shown in figure. What will be the coordinates of centre of mass of the system?


Three rods of the same mass are placed as shown in figure. What will be the coordinates of centre of mass of the system?


Two blocks
and
are connected by a massless string (shown in figure). A force of 30 N is applied on block
. The distance travelled by centre of mass in 2 s starting from rest is

Two blocks
and
are connected by a massless string (shown in figure). A force of 30 N is applied on block
. The distance travelled by centre of mass in 2 s starting from rest is

Find the velocity of centre of the system shown in the figure.

Find the velocity of centre of the system shown in the figure.

The blocks
and
, each of mass
, are connected by massless spring of natural length
and spring constant
. The blocks are initially resting on a smooth horizontal floor with the spring at its natural length, as shown in figure. A third identical block
, also of mass
, moves on the floor with a speed
along the line joining
and
, and collides with
. Then

Further loss in KE> = gain in elastic potential energy
The blocks
and
, each of mass
, are connected by massless spring of natural length
and spring constant
. The blocks are initially resting on a smooth horizontal floor with the spring at its natural length, as shown in figure. A third identical block
, also of mass
, moves on the floor with a speed
along the line joining
and
, and collides with
. Then

Further loss in KE> = gain in elastic potential energy
A set of
identical cubical blocks lies at rest parallel to each other along a line on a smooth horizontal surface. The separation between the near surfaces of any two adjacent blocks is
. The block at one end is given a speed
towards the next one at time
. All collision are completely elastic. Then

Since collision is 100% elastic, now first block comes to rest and 2nd block starts moving towards the 3rd block with a velocity
Finally only the last
A set of
identical cubical blocks lies at rest parallel to each other along a line on a smooth horizontal surface. The separation between the near surfaces of any two adjacent blocks is
. The block at one end is given a speed
towards the next one at time
. All collision are completely elastic. Then

Since collision is 100% elastic, now first block comes to rest and 2nd block starts moving towards the 3rd block with a velocity
Finally only the last
Which of the following noble gas was reacted with
by Bartlett to prepare the first noble gas compounds -
Which of the following noble gas was reacted with
by Bartlett to prepare the first noble gas compounds -
In the given figure, two bodies of mass
and
are connected by massless spring of force constant
and are placed on a smooth surface (shown in figure), then

In the given figure, two bodies of mass
and
are connected by massless spring of force constant
and are placed on a smooth surface (shown in figure), then

Two blocks
and
(
) are connected with a spring of force constant
and are inclined at a angel
with horizontal. If the system is released from rest, which one of the following statements is/are correct?

Two blocks
and
(
) are connected with a spring of force constant
and are inclined at a angel
with horizontal. If the system is released from rest, which one of the following statements is/are correct?

Two negatively charges particles having charges
and
and masses
and
respectively are projected one after another into a region with equal initial velocity. The electric field
is along the
-axis, while the direction of projection makes an angle a with the
-axis. If the ranges of the two particles along the
-axis are equal then one can conclude that

It means,
This is possible when
Two negatively charges particles having charges
and
and masses
and
respectively are projected one after another into a region with equal initial velocity. The electric field
is along the
-axis, while the direction of projection makes an angle a with the
-axis. If the ranges of the two particles along the
-axis are equal then one can conclude that

It means,
This is possible when
A particle of mass
moves in the
plane with a velocity
along the straight line
. If the angular momentum of the particle with respect to origin
is
when it is at
and
when it is at
, then


Therefore, the magnitude of
where
A particle of mass
moves in the
plane with a velocity
along the straight line
. If the angular momentum of the particle with respect to origin
is
when it is at
and
when it is at
, then


Therefore, the magnitude of
where
In the given figure four identical spheres of equal mass are suspended by wires of equal length
, so that all spheres are almost touching to each other. If the sphere 1 is released from the horizontal position and all collisions are elastic, the velocity of sphere 4 just after collision is
Or
Or
Since, all collisions are elastic, so velocity of sphere 1 is transferred to sphere 2, then from 2 to 3 and finally from 3 to 4. Hence, just after collision, the sphere 4 attains a velocity equal to
In the given figure four identical spheres of equal mass are suspended by wires of equal length
, so that all spheres are almost touching to each other. If the sphere 1 is released from the horizontal position and all collisions are elastic, the velocity of sphere 4 just after collision is
Or
Or
Since, all collisions are elastic, so velocity of sphere 1 is transferred to sphere 2, then from 2 to 3 and finally from 3 to 4. Hence, just after collision, the sphere 4 attains a velocity equal to