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 $N _1 \tan \theta=\frac{ mg }{2}$

With what minimum velocity should block be projected from left end $A$ towards end $B$ such that it reaches the other end $B$ of conveyer belt moving with constant velocity $v$. Friction coefficient between block and belt is $\mu$ .

A block of mass $10\, kg$ moving at $10\,m/s$ is released to slide on rough surface having  coefficient of friction $0.2.$ It will stop by travelling distance ........ $m$

A stone weighing $1$ kg and sliding on ice with a velocity of $2$ m/s is stopped by friction in $10$ sec. The force of friction (assuming it to be constant) will be ......... $N$

Determine the maximum acceleration in $m/s^2$ of the train in which a box lying on its floor will remain stationary, given that the co-efficient of static friction between the box and the train’s floor is $0.15.$

A body takes $1\frac{1}{3}$ times as much time to slide down a rough identical but smooth inclined plane. If the angle of inclined plane is $45^o$, the coefficient of friction is