Two blocks of masses 3 $m$ and 2 $m$ are in contact on a smooth table. A force $P$ is first applied horizontally on block of mass 3 $m$ and then on mass $2\ m$. The contact forces between the two blocks in the two cases are in the ratio [image:5_image48.emf]

Question

Dr. Abubacker · Accepted Answer

(b) If $f_{1}$ is the contact force in the first case, then
$f_{1} = (2m)$ (acceleration)
$= 2m 	imes \frac{P}{5m} = \frac{2P}{5}$
If $f_{2}$ is the contact force in the second case, then
$f_{2} = (3m)$ (acceleration)
$= 3m 	imes \frac{P}{5m} = \frac{3P}{5}$
Required ratio is $\frac{2P}{5}:\frac{3P}{5}$ or 2 : 3
Note that the total acceleration of the system is the same as the acceleration of mass 2$m$ or mass 3$m$

Q. Two blocks of masses 3 $m$ and 2 $m$ are in contact on a smooth table. A force $P$ is first applied horizontally on block of mass 3 $m$ and then on mass $2\ m$. The contact forces between the two blocks in the two cases are in the ratio

Explanation

Reviewed by Dr. Abubacker

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