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प्रश्न
Consider the situation shown in figure. The wall smooth but the surface of A and B in contact are rough. The friction on B due to A in equilibrium
विकल्प
is upward
is downward
is zero
the system cannot remain in equilibrium.
उत्तर
the system cannot remain in equilibrium.
Since the wall is smooth and the surface of A and B in contact are rough, the net vertical force on the system is in the downward direction. Hence, the system cannot remain in equilibrium.
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