Chapter 6 – System of Particles and Rotational Motion
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A particle of mass m is moving in YZ-plane with a uniform velocity v a with its trajectory running parallel to + ve Y-axis and intersecting Z-axis at z = an in a figure. The change in its angular momentum about the origin it bounces elastically from a wall at y = constant
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Nov
A particle of mass m is moving in YZ-plane with a uniform velocity v a with its trajectory running parallel to + ve Y-axis and intersecting Z-axis at z = an in a figure. The change in its angular momentum about the origin it bounces elastically from a wall at y = constant Which of [...]
Which of the following points is the likely position of the centre of mass of the system shown in Fig.
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Nov
Which of the following points is the likely position of the centre of mass of the system shown in Fig. Which of the following points is the likely position of the centre of mass of the system shown in Fig. November 27, 2020 Category: Chapter 6 - System of Particles and Rotational Motion , NCERT [...]
A cylinder of mass 10 kg and radius 15 cm is rolling perfectly on a plane of inclination 30^o . The coefficient of static friction μs = 0.25. (a) How much is the force of friction acting on the cylinder ? (b) What is the work done against friction during rolling ? (c) If the inclination θ of the plane is increased, at what value of θ does the cylinder begin to skid, and not roll perfectly ?
27
Nov
A cylinder of mass 10 kg and radius 15 cm is rolling perfectly on a plane of inclination 30^o . The coefficient of static friction μs = 0.25. (a) How much is the force of friction acting on the cylinder ? (b) What is the work done against friction during rolling ? (c) If the [...]
A disc rotating about its axis with angular speed ωo is placed lightly (without any translational push) on a perfectly frictionless table. The radius of the disc is R. What are the linear velocities of the points A, B and C on the disc shown in Fig. 7.41? Will the disc roll in the direction indicated?
27
Nov
A disc rotating about its axis with angular speed ωo is placed lightly (without any translational push) on a perfectly frictionless table. The radius of the disc is R. What are the linear velocities of the points A, B and C on the disc shown in Fig. 7.41? Will the disc roll in the direction [...]
A bullet of mass 10 g and speed 500 m/s is fired into a door and gets embedded exactly at the center of the door. The door is 1.0 m wide and weighs 12 kg. It is hinged at one end and rotates about a vertical axis practically without friction. Find the angular speed of the door just after the bullet embeds into it.
27
Nov
A bullet of mass 10 g and speed 500 m/s is fired into a door and gets embedded exactly at the center of the door. The door is 1.0 m wide and weighs 12 kg. It is hinged at one end and rotates about a vertical axis practically without friction. Find the angular speed of [...]
A man stands on a rotating platform, with his arms stretched horizontal holding a 5kg weight in each hand. The angular speed of the platform is 30 revolutions per minute. The man then brings his arms close to his body with the distance of each weight from the axis changing from 90cm to 20cm. moment of inertia of the man together with the platform may be taken to be constant and equal t 7.6kgm2. (a) What is the his new angular speed ? (Neglect friction.) (b) Is kinetic energy conserved in the process ? If not, from where does the change come about ?
27
Nov
A man stands on a rotating platform, with his arms stretched horizontal holding a 5kg weight in each hand. The angular speed of the platform is 30 revolutions per minute. The man then brings his arms close to his body with the distance of each weight from the axis changing from 90cm to 20cm. moment [...]
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Chapter 6 - System of Particles and Rotational Motion
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NCERT Exemplar Class 11
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A man stands on a rotating platform ,
an engine needs to transmit a torque of 180 N m. What is the power required by the engine ? (Note: uniform angular velocity in the absence of friction implies zero torque. In practice ,
applied torque is needed to counter frictional torque). Assume that the engine is 100% efficient. ,
To maintain a rotor at a uniform angular speed of 200 rad s^−1 ,
A sphere rolls up an inclined plane whose inclination is 30^∘. At the bottom of the inclined plane, the center of mass of the sphere has a translational speed of 5ms^−1 (a) How far does the sphere travel up the plane? (b) How long does it take to return to the bottom?
27
Nov
A sphere rolls up an inclined plane whose inclination is 30^∘. At the bottom of the inclined plane, the center of mass of the sphere has a translational speed of 5ms^−1 (a) How far does the sphere travel up the plane? (b) How long does it take to return to the bottom? A sphere rolls [...]
The oxygen molecule has a mass of 5.30×10^−26kg and a moment of inertia of 1.94×10^−46kgm^2 about an axis through its centre perpendicular to the line joining the two atoms. Suppose the mean speed of such a molecule in a gas is 500m/s and that its kinetic energy of rotation is two/thirds of its kinetic energy of translation. Find the average angular velocity of the molecule.
27
Nov
The oxygen molecule has a mass of 5.30×10^−26kg and a moment of inertia of 1.94×10^−46kgm^2 about an axis through its centre perpendicular to the line joining the two atoms. Suppose the mean speed of such a molecule in a gas is 500m/s and that its kinetic energy of rotation is two/thirds of its kinetic energy [...]
Posted in:
Chapter 6 - System of Particles and Rotational Motion
,
NCERT Exemplar Class 11
,
Physics
,
Tags:
an engine needs to transmit a torque of 180 N m. What is the power required by the engine ? (Note: uniform angular velocity in the absence of friction implies zero torque. In practice ,
applied torque is needed to counter frictional torque). Assume that the engine is 100% efficient. ,
To maintain a rotor at a uniform angular speed of 200 rad s^−1 ,
A hoop of radius 2m weight 100kg. It rolls along a horizontal floor so that its centre of mass has a speed of 20cms^−1. How much work has to be done to stop it ?
27
Nov
A hoop of radius 2m weight 100kg. It rolls along a horizontal floor so that its centre of mass has a speed of 20cms^−1. How much work has to be done to stop it ? A hoop of radius 2m weight 100kg. It rolls along a horizontal floor so that its centre of mass has [...]
From a uniform disc of radius R, a circular section of radius R/2 is cut out. The centre of the hole is at R/2 from the centre of the original disc. Locate the centre of mass of the resulting flat body.
27
Nov
From a uniform disc of radius R, a circular section of radius R/2 is cut out. The centre of the hole is at R/2 from the centre of the original disc. Locate the centre of mass of the resulting flat body. a circular section of radius R/2 is cut out. The centre of the hole [...]