Answer:
The right answer for this question is 85%.
(I had the same question.)
The impulse is given by the magnitude of the force times the time interval:
We can see that the force F of the 4 skateboard is always the same (33 N), this means that the skateboard with greatest impulse is the one with the largest time interval, so skateboard C).
The force on the clove will have the same magnitude but a negative sign with it that is F = - 14 N
<h3>What is force and how do we calculate it ?</h3>
The definition of force is: The pushing or pulling on a massed object changes its velocity. Force is an external agent that has the power to alter a body's resting or moving condition.
It has a size and a movement.
Newton's second law of motion defines the force formula as follows:
A force is equal to an object's mass times its acceleration, or F = m a. You must use SI units when applying this formula: kilograms for mass, meters per second squared for acceleration, and newtons for force.
To know more about force you may visit the link which is :
brainly.com/question/26115859
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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
