The coefficient of friction is 0.39
Explanation:
The equation of the forces along the direction parallel to the incline is the following:
(1)
where
is the component of the weight parallel to the incline (acting downward), with
m = 50 kg being the mass of the couch
(acceleration of gravity)
is the angle of the ramp
is the force of friction, acting up along the plane, with
being the coefficient of friction
N is the normal force
is the acceleration
The equation of the forces along the direction perpendicular to the plane is
(2)
where
is the component of the weight perpendicular to the plane
From (2) we find
![N=mg cos \theta](https://tex.z-dn.net/?f=N%3Dmg%20cos%20%5Ctheta)
And substituting into (1)
![mg sin \theta - \mu mg cos \theta = ma](https://tex.z-dn.net/?f=mg%20sin%20%5Ctheta%20-%20%5Cmu%20mg%20cos%20%5Ctheta%20%3D%20ma)
And solving for
, we find
![\mu = \frac{g sin \theta - a}{g cos \theta}=\frac{(9.8)(sin 25^{\circ}-0.70}{(9.8)(cos 25^{\circ})}=0.39](https://tex.z-dn.net/?f=%5Cmu%20%3D%20%5Cfrac%7Bg%20sin%20%5Ctheta%20-%20a%7D%7Bg%20cos%20%5Ctheta%7D%3D%5Cfrac%7B%289.8%29%28sin%2025%5E%7B%5Ccirc%7D-0.70%7D%7B%289.8%29%28cos%2025%5E%7B%5Ccirc%7D%29%7D%3D0.39)
Learn more about inclined planes:
brainly.com/question/5884009
#LearnwithBrainly
Answer:
Explanation:
Convert the mass to kg:
375g = 375/1000kg = 0.375kg
F = ma
-20 = 0.375a
a = -20/0.375
a = -53
The object is accelerating at 53m/s/s backwards assuming that the forward motion is positive.
Answer: 0.6
Explanation:
If we draw a free body diagram of the box we will have the following:
Net force in the x-axis:
(1)
Net force in the y-axis:
(2)
Where:
is the normal force
is the weight of the box
is the force exerted on the box
is the angle below the horizontal
is the friction force, being
the coefficient of kinetic friction
Isolating
from (1):
(3)
Substituting (3) in (2):
(4)
Finding
:
(5)
(6)
Finally:
(5)
Answer:
Missing 0.4 what you need is 8.4
Explanation: