Answer:
(A) 60 J
Explanation:
At state 1
KE₁=100 J
At state 2
KE₂ = 0
U₂=80 J
Given that surface is rough so friction force will act in opposite to the direction of motion
Lets take work done by friction = Wfr
From work power energy
Work done by all forces = Change in kinetic energy
Wfr + U₂=ΔKE
Wfr+80 = 100
Wfr= 20 J
Now when book slides from top position then
Wfr+ U = KEf - KEi
-20 + 80 = KEf-0
KEf= 60 J
(A) 60 J
u might be right
........................jljhhhhhhhhhhj
Particles that are closely packed but spaced apart enough to move over one another are called plasma. Option C is correct.
<h3>What is the plasma state of matter?</h3>
Plasma is a state of matter wherein particles are tightly packed but are far enough apart to slide over one another.
The following conditions are followed by the plasma state.
Hence, option C is correct.
To learn more about the plasma state refer;
brainly.com/question/5496865
#SPJ1
The correct answer is the Sun.i hope that helped! if you have any questions or concerns about the answer i gave you please let me know!!
