hi dsy5037! welcome to pf! :smile:
your method is correct, but you've not thought out the PE difference correctly …
not all the 1.6 m of string has fallen 1.6 m, has it? :wink:
you are fundamentally misunderstanding what it means for a force to act on a body :redface:
there are two forces acting on the mass:
i] its weight, mg vertically down
ii] the reaction force from the rod, mg vertically up
these forces balance, and so the mass stays where it is
there are...
Hi Fantasist! :smile:
Sorry, but this is meaningless :redface: …
the gravitational force acts through the mass m, and has nothing to do with the rail.
(If you mean the reaction force, it is always perpendicular to the frictionless rail, and so does no work.)
hi subzero0137! :smile:
the acceleration will be less than gsinα
because the constant gravitational component of force is opposed by the velocity-dependent electromagnetic force :wink:
yes this is correct
21/7 miles minus 20/7 miles = 1/7 miles west
14/7 miles minus 15/7 miles = minus 1/7 miles east = 1/7 miles west
either way you get 1/7 miles west :smile:
i don't understand what you're not getting about this :confused: