Explanation:
(a) Net force acting on the block is as follows.

or, ma = -mg Sin (\theta)[/tex]
a = 
= 
= -3.35 
According to the kinematic equation of motion,

Distance traveled by the block before stopping is as follows.
s = 
= 
= 21.5 m
According to the kinematic equation of motion,
v =
0 = 
= 7.16 sec
Therefore, before coming to rest the surface of the plane will slide the box till 7.16 sec.
(b) When the block is moving down the inline then net force acting on the block is as follows.

ma = 
a = 
= 
= 3.35 
Kinematics equation of the motion is as follows.
s = 
21.5 m = 
= 
= 3.58 sec
Hence, total time taken by the block to return to its starting position is as follows.
t = 
= 7.16 sec + 3.58 sec
= 10.7 sec
Thus, we can conclude that 10.7 sec time it take to return to its starting position.
That ratio is 2 .
<h3>What is ratio?</h3>
A ratio is the comparison of the two numbers bydivision.
Taking the first two outputs, or the -1/8 and -1/4, we can divide not the second one by the first one to find the
ratio:
-1/4-1/8
When dividing fractions, we multiply by the reciprocal:
-1/4x-8/1
To multiply fractions, multiply straight across:
(-1x-8)/(4x1) 8/4=2
To know more about ratio click-
brainly.com/question/25927869
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The Joule is the SI unit of energy.
Work = Force* Distance
2000*1000=2000000
Power = Work/Time
2000000/45=<span>44444.44 Watts</span>