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Can we make this quick I gotta have this question done really quick thank you

Can we make this quick I gotta have this question done really quick thank you-example-1
User Fayyaz Ali
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1 Answer

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The given problem can be exemplified in the following diagram:

In the diagram we have the following forces:


\begin{gathered} F=\text{ pushing force} \\ F_x=\text{ x-component of the force} \\ F_y=\text{ y-component of the force} \\ N=\text{ normal force} \\ F_f=\text{ friction force} \\ W=\text{ weight} \end{gathered}

Now we will determine the value of the acceleration of the box. To do that we will add the forces in the horizontal direction:


\Sigma F_h=F_x-F_f

According to Newton's second law we have that the sum of forces must be equal to the product of the mass and the acceleration:


F_x-F_f=ma

To determine the value of the friction force we use the following relationship:


F_f=\mu N

To determine the value of the normal force we add the forces in the vertical direction:


\Sigma F_v=N-F_y-W

Since there is no movement in the vertical direction we have:


N-F_y-W=0

Now we solve for the normal force:


N=F_y+W

To determine the vertical component of the force we use the right triangle shown in the diagram. We use the function sine and we get:


\sin 35.7=(F_y)/(F)

Now we multiply both sides by "F":


F\sin 35.7=F_y

Now we substitute this value in the formula for the normal force:


N=F\sin 35.7+W

Now we substitute this value in the formula for the friction force:


F_f=\mu(F\sin 35.7+W)

Now we substitute this value in the formula for the horizontal forces:


F_x-\mu(F\sin 35.7+W)=ma

Now, to determine the horizontal component of the force we use the function cosine:


\cos 35.7=(F_x)/(F)

Now we multiply both sides by "F":


F\cos 35.7=F_x

Now we substitute in the sum of horizontal forces:


F\cos 35.7-\mu(F\sin 35.7+W)=ma

Now we solve for "a" by dividing both sides by "m":


(F\cos 35.7-\mu(F\sin 35.7+W))/(m)=a

To determine the mass we use the formula for the weight:


W=mg

Where:


g=\text{ acceleration of gravity}

Now we divide both sides by "g";


(W)/(g)=m

Now we substitute the values:


((401N)\cos 35.7-(0.587)(401N\sin 35.7+245N))/((245N)/(9.8(m)/(s^2)))=a

Solving the operations we get:


1.779(m)/(s^2)=a

Now, we will determine the final velocity of the movement. We will use the following equation of motion:


2ad=v^2_f-v^2_0

Since the box starts from rest this means that the initial velocity is zero:


2ad=v^2_f

Now we take the square root to both sides:


\sqrt[]{2ad}=v_f

Now we substitute the values:


\sqrt[]{2(1.779(m)/(s^2))(3.37m)}=v_f

Solving the operations:


3.46(m)/(s)=v_f

Now we use the following equation of motion to determine the time:


v_f=v_0+at

Since the initial velocity is zero:


v_f=at

Now we divide by the acceleration:


(v_f)/(a)=t

Substituting the values:


(3.46(m)/(s))/(1.779(m)/(s^2))=t

Solving the operations:


1.94s=t

Therefore, it takes the box 1.94 seconds to move.

Can we make this quick I gotta have this question done really quick thank you-example-1
User Sahil Gulati
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