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3 years ago

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Three boxes rest side-by-side on a smooth, horizontal floor. Their masses are 5.0 kg, 3.0 kg, and 2.0 kg, with the 3.0-kg mass i

n the center. A force of 50 N pushes on the 5.0-kg box, which pushes against the other two boxes. What magnitude force does the 5.0-kg box exert on the 3.0-kg box?

1 answer:

Fed [463]3 years ago

6 0

Answer:25 N

Explanation:

Given

mass of 5 , 3 & 2 kg blocks lie on floor

Force on 50 N pushes the 5 kg box

$Let N_1$ be the reaction on 2 kg box therefore

$N_1=2\times a$

where a is the acceleration of the system

$N_2=$ reaction on 3 kg block by 5 kg block

$N_2-N_1=3a$

$N_2=5a$

Now for 5 kg block

$F-N_2=5a$

F=10a

$a=\frac{F}{10}=5 m/s^2$

Force exerted by 5 kg block on 3 kg block is

$N_2=5\times 5=25 N$

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