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3 years ago

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g Larry , Moe, and Curly are pushing on a 25 kg crate. The crate is sitting on a horizontal floor, and the coefficient of kineti

c friction between the floor and the crate is 0.25. Larry pushes to the right with a force of 400 N. Moe pushes to the left with a force of 250 N. Curly pushes straight downward on the crate with a force of 150 N. What is the acceleration of the crate

1 answer:

kobusy [5.1K]3 years ago

7 0

Answer: $2.05 m/s^2$

Explanation:

Given

Mass of crate is $m=25\ kg$

coefficient of kinetic friction $\mu _k=0.25$

Larry Pushes with a force of $F_L=400\ N$ to the right

Moe pushes with a force of $F_m=250\ N$ to the left

Curly Pushes downward with a force of $F_c=150\ N$

Net Normal reaction on the ground is

$N=mg+F_c$

$N=25\times 9.8+150=395\ N$

Friction force is given by $f=\mu _k\cdot N$

$f=0.25\times 395$

$f=98.75\ N$

Friction Force always opposes the motion

Net Horizontal force on the box is

$F_{net}=400-250-98.75$

$F_{net}=51.25\ N$

acceleration is given by

$a=\frac{F_{net}}{m}$

$a=\frac{51.25}{25}$

$a=2.05\ m/s^2$

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