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What are Eulerian angles? A body with rotational symmetry about an axis is rotating under gravity about a point on the axis without friction. What are the quantities remaining constant during the motion? Find them in terms of suitable Eulerian angles. Explain 'precession' and 'nutation' of such a body.
(ii) At what velocity, the electron momentum will be m_0 c?
(i) An electron of rest mass m_0 moves with a velocity v such that its total energy is double of its rest mass energy. What is the electron velocity?
What is the significance of the null result of Michelson-Morley experiment? Does it disprove the existence of ether? Justify.
A planet revolves around the Sun in an elliptic orbit of eccentricity e. If T is the time period of the planet, find the time spent by the planet between the ends of the minor axis close to the Sun.
When a sphere of radius r falls down a homogeneous viscous fluid of unlimited extent with the terminal velocity v, the retarding viscous force acting on the sphere depends on the coefficient of viscosity \eta, the radius r and its velocity v. Show how Stokes' law was arrived at connecting these quantities from the dimensional considerations.
(ii) Which term in the above equation represents the Coriolis force?
(iii) Discuss the important role of Coriolis forces in the circulation pattern of winds.
Show that the magnitudes of the centripetal and Coriolis accelerations of the earth while rotating counter-clockwise about the north pole are around 0\cdot 034\text{ m sec}^{-2} and (1\cdot 46 \times 10^{-4} v)\text{ m sec}^{-2}, respectively. In obtaining these results, consider the ratio of sidereal days to solar days in a year as (366\cdot 5/365\cdot 5) and the radius of the earth along the equator as 6400\text{ km}.
(i) For a particle of mass m moving with velocities \vec{v}_s and \vec{v}_r relative to the space and rotating axis, respectively, show that the equation of motion is obtained as \vec{F}-2m(\vec{\omega}\times\vec{v}_r)-m\vec{\omega}\times(\vec{\omega}\times\vec{r}) = m\vec{a}_r with \vec{\omega} and \vec{a}_r being the angular velocity and acceleration in rotating coordinates.
Two bodies of masses M_1 and M_2 are placed at a distance d apart. Show that at this position where the gravitational field due to them is zero, the potential is given by V = -\frac{G}{d} (M_1 + M_2 + 2\sqrt{M_1 M_2})
Obtain Poiseuille's equation for a viscous fluid flowing through a narrow tube of radius r and length l. If a spherical body of radius a is allowed to move at a speed \vec{V} through the same fluid of viscosity \eta, show that the viscous force will increase with the speed linearly.
Show that for any rigid body consisting of at least three particles, not arranged in one straight line, number of independent degrees of freedom is six. Define Euler's angles \theta, \phi and \psi to describe the configuration of such a rigid body. Consider two frames of reference, one fixed to the body and the other to the space defined as S' = (x', y', z') and S = (x, y, z) respectively. Show that the angular momentum (\vec{L}) of the rigid body in the two frames are related by \left( \frac{d\vec{L}}{dt} \right)_S = \left( \frac{d\vec{L}}{dt} \right)_{S'} + \vec{\omega} \times \vec{L} where \vec{\omega} is the angular velocity of rotation.
Show that the total energy per unit mass of liquid flowing from one point to another without any friction remains constant throughout the displacement.
Consider a spherical shell of mass M and radius R. Calculate the potential due to this shell at a point P when the point is (i) outside the shell and (ii) inside the shell (r < R). If the spherical shell is now replaced by a uniform solid sphere of same mass and radius, what will be its potential at the same external point?
Obtain the relativistic equation for aberration of light using velocity transformation equations.
Show that a four-dimensional volume element dx\,dy\,dz\,dt is invariant to Lorentz transformation.
A force field is given by \bar{F} = (2xy + z^3)\hat{i} + x^2\hat{j} + 3xz^2\hat{k}. Is it a conservative field ? If so, what is the scalar potential ?
Derive an expression for the moment of inertia of a rigid body about any axis. What is an "ellipsoid of inertia" ? Explain clearly what you mean by the terms "principal axes" and "principal moments of inertia" ? Find the moment of inertia of a thin rectangular lamin a about an axis passing through the centre of the lamina and perpendicular to its plane. Hence determine the moments of inertia about axes passing through the midpoints of its both sides and perpendicular to its plane.
Derive an expression for the radial and transverse components of the acceleration of a particle moving in a plane. What inferences would you draw regarding the angular momentum if the transverse acceleration is zero ?