Page 91 - Introduction to Continuum Mechanics
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76 Problems

           Let a coordinate frame e 1 ,C2,e 3 be attached to a rigid body which is spinning with an angular
        velocity ft». Then, the angular momentum vector H c, in respect to the mass center, is given by


        and




        (d) Let to = a)ft and demonstrate that




        and that




        2C1. Prove the identities (2C1.2a-e) of Section 2C1.
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        2C2. Consider the scalar field defined by <f) = x +3xy+2z.
        (a) Find a unit normal to the surface of constant 0 at the origin (0,0,0).

        (b) What is the maximum value of the directional derivative of 0 at the origin
        (c) Evaluate ctyldr at the origin if dr = ds(ei+e^).
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        2C3. Consider the ellipsoid defined by the equationx /a +y /b +z /c -l.
        Find the unit normal vector at a given position (xyz).
        2C4. Consider a temperature field given by 6 = 3xy.
        (a) Find the heat flux at the point,4(l,l,l) if q = ~kV6.
        (b) Find the heat flux at the same point as part (a) if q = -KV0, where




        2C5. Consider an electrostatic potential given by 0 = a[jecos#+,ysin#j, where a and 0 are
        constants.
        (a) Find the electric field E if E = - V0.

        (b) Find the electric displacement D if D = eE, where the matrix of e is





        (c) Find the angle 0 for which the magnitude of D is a maximum.
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