A120-meter-long ski ift carries skiers from a station at the foot of a slope to a second station 40 m above. what is the ima (ideal machincal advantage) of the lift?

Clothes dryer uses about 7 amps of current from a 240 volt line. how much power does it use?

How does changing the frequency affect the energy of the wave?

The center of a long frictionless rod is pivoted at the origin, and the rod is forced to rotate in a vertical plane with constant angular velocity \omega. write down the lagrangian for a bead of mass m threaded on the rod, using r as your generalized coordinate, where r, \phi are the polar coordinates of the bead. (notice that \phi is not an independent variable since it is fixed by the rotation of the rod tobe \phi = \omega * t) solve lagrange's equation for r(t). what happens if the bead is initially at rest at the origin? if it is released from any point ro > 0, show that r(t) eventually grows exponentially. explain your results in terms of the centrifugal force m* \omega ^2 *r.