how much work did the movers do (horizontally) pushing a 160-kg crate 10.3 m across a rough floor without acceleration, if the effective coefficient of friction was 0.50?

Respuesta :

Answer:

The work done is 8075.2 J.

Explanation:

Given that,

Mass of crate = 160 kg

Distance = 10.3 m

coefficient of friction = 0.50

We need to calculate the normal force

Using balance equation

[tex]F_{y}=ma_{y}[/tex]

[tex]F_{N}-F_{g}=ma_{y}[/tex]

Here, acceleration a = 0

[tex]F_{N}=F_{g}[/tex]

[tex]F_{N}=mg[/tex]

Put the value into the formula

[tex]F_{N}=160\times9.8[/tex]

[tex]F_{N}=1568\ N[/tex]

We need to calculate the frictional force

Using balance equation

[tex]F_{x}=ma_{x}[/tex]

[tex]F_{p}-f_{kx}=0[/tex]

[tex]F_{p}=\mu mg[/tex]

[tex]F_{p}=0.50\times160\times9.8[/tex]

[tex]F_{p}=784\ N[/tex]

We need to calculate the work done

Using formula of work done

[tex]W=F_{p}\ d\cos\theta[/tex]

[tex]W=784\times10.3\cos0[/tex]

[tex]W=8075.2\ J[/tex]

Hence, The work done is 8075.2 J.