Advertisements
Advertisements
Question
A stone is tied to one end of a string. Holding the other end, the string is whirled in a horizontal plane with progressively increasing speed. It breaks at some speed because ______
Options
The gravitational forces of the earth are greater than the tension in the string
The required centripetal force is greater than the tension sustained by the string
The required centripetal force is lesser than the tension in the string
The centripetal force is greater than the weight of the stone
Solution
A stone is tied to one end of a string. Holding the other end, the string is whirled in a horizontal plane with progressively increasing speed. It breaks at some speed because The required centripetal force is greater than the tension sustained by the string.
RELATED QUESTIONS
Obtain an expression for the torque acting on a rotating body with constant angular acceleration. Hence state the dimensions and SI unit of torque.
Obtain an expression for torque acting on a body rotating with uniform angular acceleration.
Define moment of inertia. State its SI unit and dimensions.
A flywheel is revolving with a constant angular velocity. A chip of its rim breaks and flies away. What will be the effect on its angular velocity?
A flywheel of mass 8 kg and radius 10 cm rotating with a uniform angular speed of 5 rad/sec about its axis of rotation, is subjected to an accelerating torque of 0.01 Nm for 10 seconds. Calculate the change in its angular momentum and change in its kinetic energy.
An electron(e) is revolving in a circular orbit of radius r in the hydrogen atom. The angular momentum of the electron is (M = magnetic dipole moment associated with it and m = mass of electron)
If the angular momentum of a body increases by 50%, then its kinetic energy of rotation increases by ______ (M.I. remains constant)
A thin metal wire of length 'L' and uniform linear mass density 'ρ' is bent into a circular coil with 'O' as centre. The moment of inertia of a coil about the axis XX' is ______.
The angular momentum of electron in hydrogen atom is proportional to ____________.
Two bodies with moments of inertia I1 and I2 (I1 > I2) have equal angular momenta. lf E1 and E2 are their rotational kinetic energies respectively, then ____________.
The ratio of the dimensions of Planck's constant to that of moment of inertia is the dimensions of ______.
If the angular momentum of an electron is `vec"J"` then the magnitude of the magnetic moment will be ____________.
Let I1 and I2 be the moments of inertia of two bodies of identical geometrical shape. If the first body is made of aluminium and the second of iron, then ____________.
An electron of mass 'm' revolving around the nucleus in a circular orbit of radius 'r' has angular momentum 'L'. The magnetic field produced by the electron at the centre of the orbit is e = electric charge, µ0 = permeability of free space ____________.
If E, M and P are the kinetic energy, mass and linear momentum of a particle respectively, which of the following relations represents the angular momentum L of the particle when the particle rotates in a circle of radius R?
Three-point masses each of mass 'M' are placed at the corners of an equilateral triangle of side 'a'. The moment of inertia of this system about an axis passing through one side of a triangle is ______.
A wheel of moment of inertia 2 kg m2 is rotating about an axis passing through centre and perpendicular to its plane at a speed 60 rad/s. Due to friction, it comes to rest in 5 minutes. The angular momentum of the wheel three minutes before it stops rotating is ______.
A disc of moment of inertia 'I1' is rotating in horizontal plane about an axis passing through a centre and perpendicular to its plane with constant angular speed 'ω1'. Another disc of moment of inertia 'I2' having zero angular speed is placed co-axially on a rotating disc. Now, both the discs are rotating with constant angular speed 'ω2'. The energy lost by the initial rotating disc is ______.
A body is rotating about its own axis. Its rotational kinetic energy is x and its angular momentum is y, hence its moment of inertia about the axis is ______.
The difference in the angular momentum of an electron in two successive orbits of a hydrogen atom is ______.
The angular momentum of the electron in the second orbit of hydrogen atom is L. The angular momentum in the third orbit is ______.
Define moment of inertia.
Define angular momentum.
Calculate the change in angular momentum of the electron when it jumps from third orbit to first orbit in hydrogen atom.
(Take h = 6.33 × 10−34 Js)
