- #1
AgNO3
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Homework Statement
Two rubber pads are affixed at the bottom of a box and the assembly thus formed is placed on a uniform slope of inclination 0.5 degrees. Coeff of friction is 0.60 between the pads and the plane.
Two electric motors installed in the box can make the pads move back and forth relative to the box simple harmonically in opposite phase along the line of fastest decent on the slope. Amplitude is 0.25 mm , and angular frequency ω= 72 rad/s. Soon after the motors were switched on simultaneously , the box acquires a constant velocity down the slope.
Find the magnitude of this velocity .
final answer is 0.4 mm/s .
Homework Equations
None .
The Attempt at a Solution
Well ..this question is more about correct approach so i spent lots of time thinking about the scenario , and this is what i got.
Initially , velocities are in opposite directions, so the friction will act in opposite directions. Hence net frictional force is zero. The box will move down coz of gravity.
But its given that velocity is constant, ...so i think that it may be bcoz the velocity of pads are slower than that of the box itself.
But i am not able to do anything with this conclusion i made.
Any hints ?