Chapter 9: Q4P (page 481)
Change the independent variable to simplify the Euler equation, and then find a first integral of it.
Short Answer
Answer
The first integral of the Euler equation is .
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Chapter 9: Q4P (page 481)
Change the independent variable to simplify the Euler equation, and then find a first integral of it.
Answer
The first integral of the Euler equation is .
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Write theθLagrange equation for a particle moving in a plane ifV=V(r) (that
is, a central force). Use theθequation to show that:
(a) The angular momentum r×mvis constant.
(b) The vector r sweeps out equal areas in equal times (Kepler’s second law).
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Set up Lagrange’s equations in cylindrical coordinates for a particle of mass in a potential field . Hint: ; writein cylindrical coordinates.
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