Q. Two masses of $5\, Kg$ and $3\, Kg$ are placed in contact with each other on a frictionless horizontal surface as shown in the figure. If a force of $4\, N$ is applied on the bigger mass the force on the smaller mass is

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A

4 N

B

2 N

C

0.5 N

D

1.5 N

Solution:

Let ' $a$ ' be the acceleration of the system.
$F=m a\, a=F / m=4 / 8=0.5$
Therefore force on $3\, Kg =3 \times 0.5=1.5\, N$

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