A ring of diameter 1m is rotating about a central axis perpendicular to its diameter. It is rotating with a speed of 10rad/s. What force should be applied on it tangentially to stop it in exactly 3 rotations? Let the mass of the ring be 2kg.(a) 10 N(b) 25/3π N(c) 50/3π N(d) 12.5/3 NI had been asked this question by my school principal while I was bunking the class.Origin of the question is Kinematics of Rotational Motion about a Fixed Axis in portion System of Particles and Rotational Motion of Physics – Class 11

A ring of diameter 1m is rotating about a central axis perpendicular t

1.	A ring of diameter 1m is rotating about a central axis perpendicular to its diameter. It is rotating with a speed of 10rad/s. What force should be applied on it tangentially to stop it in exactly 3 rotations? Let the mass of the ring be 2kg.(a) 10 N(b) 25/3π N(c) 50/3π N(d) 12.5/3 NI had been asked this question by my school principal while I was bunking the class.Origin of the question is Kinematics of Rotational Motion about a Fixed Axis in portion System of Particles and Rotational Motion of Physics – Class 11
Answer» Right option is (b) 25/3π N The best I can explain: Let w be the angular velocity & a be the angular acceleration. Moment of inertia of the RING = MR^2 = 20.25 = 0.5kgm^2. Angular distance = 3 ROTATIONS = 32π rad = 6π rad. Using, w^2 = w0^2 + 2aθ, we get: 0 = 100 – 2a6π. a = 100/12π. Torque = IA = rF ∴ F = Ia/r = 0.5100/(12π*0.5) = 25/3π N.

Discussion

No Comment Found

Related InterviewSolutions

A body has a moment of inertia = 5kgm^2 about an axis. What should be the torque for increasing its angular speed from 0 to 10rad/s in 4s? Assume that the body rotates purely about that axis.(a) 25Nm(b) 2.5Nm(c) 12.5Nm(d) 1.25NmThe question was posed to me at a job interview.The origin of the question is Kinematics of Rotational Motion about a Fixed Axis in portion System of Particles and Rotational Motion of Physics – Class 11
A disc of radius 10cm is rotating about the central axis perpendicular to its plane. A force of 5N acts on it tangentially. The disc was initially at rest. Calculate the value of power supplied by the force when the disc has rotated by 30°.The mass of the disc is 2kg.(a) 1.28W(b) 1.8W(c) 3.9W(d) 2.63WThe question was posed to me in exam.The doubt is from Dynamics of Rotational Motion about a Fixed Axis in section System of Particles and Rotational Motion of Physics – Class 11
Moment of inertia, of a spinning body about an axis, doesn’t depend on which of the following factors?(a) Distribution of mass around axis(b) Orientation of axis(c) Mass(d) Angular velocityI have been asked this question in semester exam.The query is from Moment of Inertia topic in section System of Particles and Rotational Motion of Physics – Class 11
A system consists of 2 particles of the same mass. Let one particle be at rest and another particle have an acceleration of “2a”. What would be the acceleration of the centre of mass of the system?(a) a/4(b) a/2(c) a(d) 2aI have been asked this question in homework.The origin of the question is System of Particles topic in section System of Particles and Rotational Motion of Physics – Class 11
The centre of mass of the body always lies on the line of symmetry for an object with uniform density.(a) True(b) FalseThe question was posed to me in homework.The above asked question is from System of Particles topic in chapter System of Particles and Rotational Motion of Physics – Class 11
For which of the following does the centre of mass lie outside the body?(a) Pen(b) Dice(c) Rectangular tile(d) BangleI have been asked this question by my school principal while I was bunking the class.My question is taken from System of Particles in portion System of Particles and Rotational Motion of Physics – Class 11
Masses 1 kg, 1.5 kg, 2 kg, and “M” kg are situated at (2,1,1), (1,2,1), (2,-2,1) and (-1,4,3). What is the value of “M” if their centre of mass is at (1,1,3/2)?(a) 1 kg(b) 1.5 kg(c) 2 kg(d) 2.5 kgThe question was asked by my college professor while I was bunking the class.This intriguing question comes from System of Particles topic in section System of Particles and Rotational Motion of Physics – Class 11
The centre of masses of two particles with masses 2 kg and 1 kg located at (1,0,1) and (2,2,0) is located at _____(a) 4/3, 2/3, 2/3(b) 2/3, 4/3, 2/3(c) 2/3, 2/3, 4/3(d) 1/3, 2/3, 2/3The question was posed to me in homework.I need to ask this question from System of Particles topic in chapter System of Particles and Rotational Motion of Physics – Class 11
The moment of inertia of a planar square about a planar axis parallel to one side is 10kgm^2. What is the moment of inertia about a diagonal?(a) 10kgm^2(b) 5kgm^2(c) 20kgm^2(d) 1kgm^2This question was posed to me in final exam.This intriguing question originated from Theorems of Perpendicular and Parallel Axes topic in chapter System of Particles and Rotational Motion of Physics – Class 11
A radioactive particle at rest, having mass 10g, breaks into 2 fragments (1&2) in the mass ratio 2:3 respectively. If the first one moves with a velocity of 10m/s what will be the speed of the second particle?(a) 4.33 m/s(b) -4.33 m/s(c) -6.67 m/s(d) 6.67 m/sThe question was asked in an online interview.Enquiry is from Linear Momentum of a System of Particles topic in portion System of Particles and Rotational Motion of Physics – Class 11

Discussion

No Comment Found

Related InterviewSolutions

Reply to Comment