Consider an elevator with a table and a book on top of the table. The mass of the table is 10kg and the mass of the book is 2kg.

At t=0 the elevator is moving up with a velocity of 1m/s.
At t=2s the elevator is moving up with a velocity of 8 m/s

Find the Force from the Book to the Table in N. Use the convention where a positive value(+) means upward force and a negative value(-) means downward force.

Consider an elevator with a table and a book on top of the table The mass of the table is 10kg and the mass of the book is 2kg At t0 the elevator is moving up w class=

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Newton's second law allows us to find the force of the block on the table is 126 N

Newton's second law says that the net force is proportional to the product of the mass and the acceleration of the body

                Σ F = m a

Where the bold letters indicate vectors, m is the mass and the acceleration of the body

A free body diagram is a diagram where the forces are represented without the details of the bodies, in the attached we can see a free body diagram of the system.

Let's start by finding the acceleration of the elevator with kinematics  

                 v = v₀ + a t

                 a = [tex]\frac{v-v_o}{a}[/tex]  

Where v and v₀ are the current and initial velocity, respectively, at acceleration and t is the time

                 a = [tex]\frac{8-1}{2}[/tex]

                 a = 3.5 m / s²

Let's write Newton's second law for each body

The book

                N₂ - W₂ + N₁ = m a

               

Table

                N₁ - W₁ - W₂ = M a

                W₁ = Mg

                W₂ = mg

                N₁ = (M + m) g + M a

                N₁ = (10 + 2) 9.8 + 10 3.5

                N₁ = 152.6 N

This is the reaction of the earth to the support of the block and the table

               N₂ = ma + m g  - N₁

               N₂ = m ( a +g) - N₁  

               N₂ = 2 (3.5 + 9.8) - 152.6

               N₂ = 26.6 - 152.6

               N₂ = -126 N

The negative sign indicates that the direction is opposite to the one assigned, this is the action of the block on the table.

In conclusion using Newton's second law we can find the forces of the block on the table is 126 N

Learn more here: brainly.com/question/19860811

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