In the figure shown, a block of weight $10 \,N$ resting on a horizontal surface. The coefficient of static friction between the block and the surface ${\mu _s} = 0.4$. A force of $3.5\, N$ will keep the block in uniform motion, once it has been set in motion. A horizontal force of $3 \,N$ is applied to the block, then the block will
A
Move over the surface with constant velocity
B
Move having accelerated motion over the surface
C
Not move
D
First it will move with a constant velocity for some time and then will have accelerated motion
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C
Not move
c (c)${F_l} = {\mu _s}R = 0.4 \times mg\, = 0.4 \times 10 = 4N$i.e. minimum $4\,N$ force is required to start the motion of a body. But applied force is only $3\,N$. So the block will not move.
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