You observe a block sliding down an incline and your careful measurements reveal
ID: 2127229 • Letter: Y
Question
You observe a block sliding down an incline and your careful measurements reveal
that the angle, ?, of the incline is 18.0o, and that the block is sliding down the incline
at a constant speed. In order to explore this interesting physical problem, you
project the block back up the ramp with an initial speed of 2.00 m/s.
a.) Find an algebraic expression (one without any numerical values) for d, the
distance that the block will slide up the incline before coming to rest.
b.) Find a numerical value for d.
c.) After the block comes to rest, will it slide down the incline again? Give an
argument to back your answer.
Explanation / Answer
NOW AS IT IS SLIDING DOWN THE INCLNE at constant spped,force due to gravitation is balanced by force due to friction.
so if friction constant is k,
then k*m*g*cos theta=m*g*sin theta
tan theta=k=0.325
now,when i send it upward,
total force=gravitational force+frictional force=2*m*g*sin 18
so acceleration=force/mass=2*g*sin 18=6.056 m/s^2 ,in downward direction
so if distance covered is d before coming to a halt:
then initial speed^2=2*deceleration*distance
d=0.33 m
c) no it wont slide back down..as static friction coefficeint is larger than dynamic friction coeffciient
so static friction will provide just enough force to balance the force due to gravitation.