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how do we derive the moment of inertia of rod, ring, disc, cylinder, sphere and cone?
show that moment of inertia of a body about an axis is numerically equal to twice that kinetic energy of rotation of the body rotating at the unit angular velocity about the axis.
what is translatory motion?
Prove that Kinetic Energy of rotation E= 1/2 IW2 WHERE SYMBOLS HAVE THEIR USUAL MEANING
please derive the centre of mass of a solid cone and a hollow cone.
pls explain m1r1= m2r2...
what is the derivation of moment of inertia of solid cone?
there is a uniform bar or mass m and length l hinged at the centre, so that it can turn in a vertical plane about a horizontal axis. Two point like masses m and 2m are rigidly attached to the ends and the arrangement is released from rest. Find (i) the initial angular acceleration of the bar (ii) the initial acceleration of mass 2m (iii) the initial reaction at hinge (iv) the angular speed aquired by the bar as it becomes vertical.
From a circular disc of radius R and mass 9m, a small disc of radius 3 is removed from the disc,the moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing through the center O?
difference between centre of gravity and centre of mass
50) 2 spherical bodies of mass M and 5M are of radii R and 2R respectively are released in free space with initial separation between their centres equal to 12R. If they attract each other due to gravitational force only, then the distance covered by the smaller bady just before collision is
a) 1.5R b)2.5R c)4.5R d)7.5R
Q. Find the torque of a force 7i+3j-5k about the origin. The force acts as on a partical whose position vector is i-j+k .
A neutron travelling with a velocity v and kinetic energy E collides elastically head on with the nucleus of an atom of mass number A at rest. The fraction of total energy retained by the neutron is
if a disc slides from top to bottom of an inclined plane ,it takes time t1.If it rolls, it takes time t2 .Now t22/t12is________
A particle performs uniform circular motion with the angular momentum L. If the frequency of the particle motion is double and its kinetic energy is half...what happens to its angular momentum???
Derive an expression for moment of inertia of a rectangular plate of sides a and b, where a is the longer side; about an axis parallel to width b and passing through the centre.
what will be the moment of inertia about an axis perpendicular to the plane of the plate passing through its centre c?
a ball moving with a speed 9m/s strikes an identical ball at rest , such that after the collisoins, the direction of each ball makes an angle of 30 degree with original line of motion.. find the speed of two balls after collisins
Derive a relation between angular momentum, moment of inertia and angular velocity of a rigid body.
The moment of inertia of two rotating bodies are IA and IB (IA IB) and their angular momenta are equal. Which one has greater kinetic energy?
0.24g of volatile liquid upon vaporisation gives 45ml of vapour at NTP .what will be the vapour density of the substance
how to calculate centre of mass of solid hemisphere
Why is the handle of a screw-driver is made wide?
state parallelogram law of vector addition. derive analytically expression for magnitude and direction of resultant vector
59) A tube of length L is filled completely woth an incompressible liquid of mass M and closed at both the ends. The tube is then rotated in a horizontal plane about one of it's ends with a uniform angular velocity w. The force exerted by the liquid at the other end is (answer in terms og M, L and w(angular velocity))
24) The moment of inertia of a disc about an axis tangential and parallel to it's surface be I, then what will be the moment of Inertia about the axis tangential but perpendicular to the surface.
25) A solid sphere ball rolls on an inclined plane without slipping. The ratio of the rotational energy and rolling energy.
v X mv =0 ??? why
Four spheres of diameter 2a and mass M each are placed with their centres at four corners of a square of side b. Calculate the moment of inertia of the system about one side of the square taken as its axis ?
system about an axis passing through, the centre of mass and normal to its plane.
Why are handles of doors fixed maximum away from the hinge end of the door?
Derive an expression for work done by torque and its power.
why moment of mass about centre is zero?
Two discs of moments of inertia I1 and I2 about their respective axes (normal to the disc and passing through the centre), and rotating with angular speeds ω1 and ω2 are brought into contact face to face with their axes of rotation coincident. (a) What is the angular speed of the two-disc system? (b) Show that the kinetic energy of the combined system is less than the sum of the initial kinetic energies of the two discs. How do you account for this loss in energy? Take ω1 ≠ ω2.
URGENT ! a child is standing at one end of a long trolley moving with a speed v on a smooth horizontal track . if the child starts running towards the other end of the trolley with a speed u , then the centre of mass of the system ( trolley + child) will move with a speed ???
find the centre of mass of three particles at the vertices of an equilateral triangle. the masses of the particles are 100g, 150g and 200g respectively. each side of the triangle is 0.5cm long. if two vertices of the triangle are (0,0) and (0.5,0). what will be the third vertex.
A bullet of mass m moving with velocity v strikes a suspended wooden block of mass M at rest. If the collision is inelastic block rises to a height h, What will the initial velocity of the bullet ?
Problem: A circular plate of uniform thickness has a diameter of 56 cm. A circular portion of diameter 42cm is removed from one edge of the plate. Find the position of the center of mass of the remaining portion.
Please reply by 13th morning, since exam on 14th morning.
What is the derivation for v=rw?
If angular momentum is conserved in a system whose moment of inertia is decreased, Will its rotational kinetic energy be also conserved? Explain.
From a square sheet of uniform density, one of the four portions within its diagonals is removed .. Find the of centre of mass of a remaining portion if the side of the square is a. The portion removed is right one
Q. A uniform rod of mass M and length a lies on a smooth horizontal plane. A partical of mass m moving at a speed v perpendicular to the length of rod strikes it at a distance a/4 from the centre and stops after the collision. Find (a) the vel. of centre of the rod and (b) the angular velocity of the rod about its centre just after the collision.
An explosion breaks a rock into three parts in a horizontal plane. Two of them go off at right angles to each other. The first part of mass 1 kg moves with a speed of 12 m/s and the second part of mass 2 kg moves with 8 m/s speed. If the third part flies off with 4 m/s speed, then its mass is??
What is the meaning of rotational analogue?
On what factors does the radius of gyration depend?
three particles each of mass m are placed at three corner of an equilateral triangle of length l. find the position of center of mass in terms of coordinates
Two identical blocks each of mass 1 kg are join together with a compressed spring. At any time after releasing they are moving with unequal speed in the opposite direction as shown in figure.
Choose the incorrect statement(s)
it is not possible
whatever may be the speed of the blocks the centre of mass will remain stationary
the centre of mass of the system is moving with a velocity of 2ms-1
the centre of mass of the system is moving with a velocity of 1 ms-1
Q. A sphere of mass m rolls without slipping on an inclined plane of inclination theta. Find the linear acceleration of the sphere and the force of friction acting on it. What should be the minimum coefficient of static friction to support pure rolling ?
A force of -F k cap acts on origint of the coordinate system. The torque about the point (1, -1) is
a) -F(i cap + j cap)
b) F(i+j)
c) -F(i-j)
d)F(i-j)
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Syllabus
how do we derive the moment of inertia of rod, ring, disc, cylinder, sphere and cone?
show that moment of inertia of a body about an axis is numerically equal to twice that kinetic energy of rotation of the body rotating at the unit angular velocity about the axis.
what is translatory motion?
Prove that Kinetic Energy of rotation E= 1/2 IW2 WHERE SYMBOLS HAVE THEIR USUAL MEANING
please derive the centre of mass of a solid cone and a hollow cone.
pls explain m1r1= m2r2...
what is the derivation of moment of inertia of solid cone?
there is a uniform bar or mass m and length l hinged at the centre, so that it can turn in a vertical plane about a horizontal axis. Two point like masses m and 2m are rigidly attached to the ends and the arrangement is released from rest. Find (i) the initial angular acceleration of the bar (ii) the initial acceleration of mass 2m (iii) the initial reaction at hinge (iv) the angular speed aquired by the bar as it becomes vertical.
From a circular disc of radius R and mass 9m, a small disc of radius 3 is removed from the disc,the moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing through the center O?
difference between centre of gravity and centre of mass
50) 2 spherical bodies of mass M and 5M are of radii R and 2R respectively are released in free space with initial separation between their centres equal to 12R. If they attract each other due to gravitational force only, then the distance covered by the smaller bady just before collision is
a) 1.5R b)2.5R c)4.5R d)7.5R
a) 200m/s3 b) 600 m/s3 c) 100 m/s2 d) 300 m/s3
Q. Find the torque of a force 7i+3j-5k about the origin. The force acts as on a partical whose position vector is i-j+k .
i)angular acceleration and
ii)angular velocity after 30 secs
A neutron travelling with a velocity v and kinetic energy E collides elastically head on with the nucleus of an atom of mass number A at rest. The fraction of total energy retained by the neutron is
if a disc slides from top to bottom of an inclined plane ,it takes time t1.If it rolls, it takes time t2 .Now t22/t12is________
A particle performs uniform circular motion with the angular momentum L. If the frequency of the particle motion is double and its kinetic energy is half...what happens to its angular momentum???
Derive an expression for moment of inertia of a rectangular plate of sides a and b, where a is the longer side; about an axis parallel to width b and passing through the centre.
what will be the moment of inertia about an axis perpendicular to the plane of the plate passing through its centre c?
pllzzz solve with the help of a diagram
a ball moving with a speed 9m/s strikes an identical ball at rest , such that after the collisoins, the direction of each ball makes an angle of 30 degree with original line of motion.. find the speed of two balls after collisins
Derive a relation between angular momentum, moment of inertia and angular velocity of a rigid body.
(1) l2√(2) l2(3) l(4) l2√
The moment of inertia of two rotating bodies are IA and IB (IA IB) and their angular momenta are equal. Which one has greater kinetic energy?
0.24g of volatile liquid upon vaporisation gives 45ml of vapour at NTP .what will be the vapour density of the substance
a) T = mg b) T = c) T = d) T = zero
how to calculate centre of mass of solid hemisphere
Why is the handle of a screw-driver is made wide?
state parallelogram law of vector addition. derive analytically expression for magnitude and direction of resultant vector
59) A tube of length L is filled completely woth an incompressible liquid of mass M and closed at both the ends. The tube is then rotated in a horizontal plane about one of it's ends with a uniform angular velocity w. The force exerted by the liquid at the other end is (answer in terms og M, L and w(angular velocity))
24) The moment of inertia of a disc about an axis tangential and parallel to it's surface be I, then what will be the moment of Inertia about the axis tangential but perpendicular to the surface.
25) A solid sphere ball rolls on an inclined plane without slipping. The ratio of the rotational energy and rolling energy.
a.√19.6 m/sec
b.√29.4 m/sec
c. 4.9 m/sec
d. 9.8 m/sec
***Inwant answer with full solution as soon as possible***
ans; 5.4m/s
v X mv =0 ??? why
Four spheres of diameter 2a and mass M each are placed with their centres at four corners of a square of side b. Calculate the moment of inertia of the system about one side of the square taken as its axis ?
(A)
(B)
(C)
(D)
system about an axis passing through, the centre of mass and normal to its plane.
Why are handles of doors fixed maximum away from the hinge end of the door?
a. 1:3
b. 1:2
c. 2:7
d. 2:5
***I want answer with full solution as soon as possible***
1. R
2.3R/2
3.2R
4.5R/2
Derive an expression for work done by torque and its power.
why moment of mass about centre is zero?
Two discs of moments of inertia I1 and I2 about their respective axes (normal to the disc and passing through the centre), and rotating with angular speeds ω1 and ω2 are brought into contact face to face with their axes of rotation coincident. (a) What is the angular speed of the two-disc system? (b) Show that the kinetic energy of the combined system is less than the sum of the initial kinetic energies of the two discs. How do you account for this loss in energy? Take ω1 ≠ ω2.
URGENT ! a child is standing at one end of a long trolley moving with a speed v on a smooth horizontal track . if the child starts running towards the other end of the trolley with a speed u , then the centre of mass of the system ( trolley + child) will move with a speed ???
acceleration of the bar immediately after it has been released from rest, knowing that the normal forces exerted on the disks are sufficient to prevent any slipping and assuming that;
(a) m = 5 kg and m' = 2kg.
(b) the mass of m' of the disks is negligible.
(c) the mass of m of the bar is negligible.
find the centre of mass of three particles at the vertices of an equilateral triangle. the masses of the particles are 100g, 150g and 200g respectively. each side of the triangle is 0.5cm long. if two vertices of the triangle are (0,0) and (0.5,0). what will be the third vertex.
a) downwards at end A
b) downwards at mid point of AB
c) downwards at at point C such that AC=1m
d) downwards at at point D such that BD=1m
A bullet of mass m moving with velocity v strikes a suspended wooden block of mass M at rest. If the collision is inelastic block rises to a height h, What will the initial velocity of the bullet ?
(a)2/3 mvol (b) 3/2 mvol (c) 5/6 mvol (d) 7/8mvol
find:
1) the angular velocity of system after the collision
2) the velocities of A and B immediately after the collision
3) the velocity of the centre of the rod when the rod rotates through 90 degree after the collision
Please provide the answer to the above given question urgently.
Problem: A circular plate of uniform thickness has a diameter of 56 cm. A circular portion of diameter 42cm is removed from one edge of the plate. Find the position of the center of mass of the remaining portion.
Please reply by 13th morning, since exam on 14th morning.
What is the derivation for v=rw?
If angular momentum is conserved in a system whose moment of inertia is decreased, Will its rotational kinetic energy be also conserved? Explain.
From a square sheet of uniform density, one of the four portions within its diagonals is removed .. Find the of centre of mass of a remaining portion if the side of the square is a. The portion removed is right one
Q. A uniform rod of mass M and length a lies on a smooth horizontal plane. A partical of mass m moving at a speed v perpendicular to the length of rod strikes it at a distance a/4 from the centre and stops after the collision. Find (a) the vel. of centre of the rod and (b) the angular velocity of the rod about its centre just after the collision.
An explosion breaks a rock into three parts in a horizontal plane. Two of them go off at right angles to each other. The first part of mass 1 kg moves with a speed of 12 m/s and the second part of mass 2 kg moves with 8 m/s speed. If the third part flies off with 4 m/s speed, then its mass is??
What is the meaning of rotational analogue?
On what factors does the radius of gyration depend?
Q.2. An infinite number of uniform discs are pivoted at their respective centres and arrange in such a manner that centres of all the discs are at the same horizontal level. Radius of biggest disc is R and successive discs have radii 1/ of radius of disc to its left. A rod having same mass as the mass of largest disc is placed over the discs, touching all of them. There is no friction between discs but friction is sufficient between rod and discs, so that rod does not slip. Acceleration of rod is
(A)
(B)
(C)
(D)
three particles each of mass m are placed at three corner of an equilateral triangle of length l. find the position of center of mass in terms of coordinates
Two identical blocks each of mass 1 kg are join together with a compressed spring. At any time after releasing they are moving with unequal speed in the opposite direction as shown in figure.
Choose the incorrect statement(s)
it is not possible
whatever may be the speed of the blocks the centre of mass will remain stationary
the centre of mass of the system is moving with a velocity of 2ms-1
the centre of mass of the system is moving with a velocity of 1 ms-1
Q. A sphere of mass m rolls without slipping on an inclined plane of inclination theta. Find the linear acceleration of the sphere and the force of friction acting on it. What should be the minimum coefficient of static friction to support pure rolling ?
A force of -F k cap acts on origint of the coordinate system. The torque about the point (1, -1) is
a) -F(i cap + j cap)
b) F(i+j)
c) -F(i-j)
d)F(i-j)