A force $\vec{F}=\hat{i}+4 \hat{j}$ acts on the block shown. The force of friction acting on the block is

212711-q

  • A

    $-\hat{i}$

  • B

    $-18 \hat{i}$

  • C

    $-2.4 \hat{i}$

  • D

    $-3 \hat{i}$

Similar Questions

A pen of mass $m$ is lying on a piece of paper of mass $M$ placed on a rough table. If the coefficients of friction between the pen and paper and the paper and the table are $\mu_1$ and $\mu_2$, respectively. Then, the minimum horizontal force with which the paper has to be pulled for the pen to start slipping is given by

  • [KVPY 2010]

In the figure, a ladder of mass $m$ is shown leaning against a wall. It is in static equilibrium making an angle $\theta$ with the horizontal floor. The coefficient of friction between the wall and the ladder is $\mu_1$ and that between the floor and the ladder is $\mu_2$. The normal reaction of the wall on the ladder is $N_1$ and that of the floor is $N_2$. If the ladder is about to slip, then

$Image$

$(A)$ $\mu_1=0 \mu_2 \neq 0$ and $N _2 \tan \theta=\frac{ mg }{2}$

$(B)$ $\mu_1 \neq 0 \mu_2=0$ and $N_1 \tan \theta=\frac{m g}{2}$

$(C)$ $\mu_1 \neq 0 \mu_2 \neq 0$ and $N _2 \tan \theta=\frac{ mg }{1+\mu_1 \mu_2}$

$(D)$ $\mu_1=0 \mu_2 \neq 0$ and $N _1 \tan \theta=\frac{ mg }{2}$

  • [IIT 2014]

The coefficient of static friction, $\mu _s$ between block $A$ of mass $2\,kg$ and the table as shown in the figure is $0.2$. What would be the maximum mass value of block $B$ so that the two blocks $B$ so that the two blocks do not move? The string and the pulley are assumed to be smooth and masseless ....... $kg$ $(g = 10\,m/s^2)$

What is the maximum value of the force $F$ such that the block shown in the arrangement, does not move ........ $N$

  • [IIT 2003]

A block of $7\,kg$ is placed on a rough horizontal surface and is pulled through a variable force $F$ (in $N$ ) $= 5\,t$ , where $'t'$ is time in second, at an angle of $37^o$ with the horizontal as shown in figure. The coefficient of static friction of the block with the surface is one. If the force starts acting at $t = 0\,s$ . Find the time at which the block starts to slide ......... $\sec$ (Take $g = 10\,m/s^2$ )