16. A block of mass m is released on the top of a
smooth inclined plane of length x and inclination theta
as shown in figure. Horizontal surface is rough. If
block comes to rest after moving a distance d on
the horizontal surface, then the coefficient of friction between the block and the surface is
Answers
Answer:
option 4 is correct. bro foollow me
Dear student,
Given:
Mass of block = m
length of incline = x
length of horizontal = d
angle of incline = ∅
Initial velocity , u = 0
final velocity, v = 0
To find:
The coefficient of friction b/w block & surface
Solution:
We know by work-energy theorem that the work done by all the forces is equal to the change in the kinetic energy.
Since the initial and final velocities are zero, hence, we can write:
W (all forces) = Δ K.E.
W (all forces) = 0
Now we include the possible forces by which the work is being done ( refer to the attached image in question ).
Wg + Wn + Wfr = 0
[ where, Wg = work done by gravity
Wn = work done by normal
Wfr = work done by friction ]
mg x sin∅ + 0 + fr d = 0
mg x sin∅ - μmg d = 0
mg x sin∅ = μmg d
μ = x sin∅/ d
Hence, option (c) x sin∅/d is correct answer.