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High.
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In the given problem, suppose the total force applied by all the 25 people on this plane is f.
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Then the total work done by the people total work done will be converted into two forms.
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One, in the form of kinetic energy.
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Of the plane as it will start moving and another work done in the form of work done against rolling friction as the distance traveled is d as the distance traveled by the plane distance moved under the applied force by the plane if supposed to be d then the total work done will be f into d which we are saying will be converted into kinetic energy means half mv square plus small f where this is small f is the force of friction into d.
01:40
So this is this f into d is the work done by the force of friction.
01:49
Now we have to find this v finally speed.
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So to find this final velocity for the time being we make it equation number one.
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Now using first equation of motion.
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Now using first equation of motion which says this v is equal to u plus a t.
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V is the final speed achieved by the plane after moving this distance of 3 .7 meter in 6 .1 seconds.
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U is the initially speed which was 0 acceleration this is not given to us and time t which is 6 .1 second.
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We will use it later on.
02:35
Now the net force acting on the plane will be the applied force in the forward direction, capital f, and force of friction in the backward direction.
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So total force will be f minus f and using newton's second law of motion that may be equated with m into a.
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So acceleration here comes out to be f minus f by m.
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M.
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M is a.
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The mass of the plane...