$A$ block of mass $4 \ kg$ is at rest on a rough inclined plane making an angle of $\theta$ with the horizontal. The coefficient of static friction between the block and the plane is $0.5$ and the frictional force on the block is $14.14 \ N$. Find the value of $\theta$. (in $^{\circ}$)

If $300\,J$ of work is done to move a $2\,kg$ block up a rough inclined plane to a height of $10\,m$,find the work done against friction in $J$. (Take $g = 10\,m/s^2$)

When a body is placed on a rough plane inclined at an angle $\theta$ to the horizontal,its acceleration is

Two blocks of masses $1 \ kg$ and $2 \ kg$ are connected by a light rod and the system is slipping down a rough incline at an angle of $45^{\circ}$ with the horizontal. The coefficient of kinetic friction at both contacts is $0.4$. If the acceleration of the system is $\alpha \sqrt{2} \ m/s^2$, find the value of $\alpha$. (Use $g = 10 \ m/s^2$)

$A$ person climbs up a conveyor belt with a constant acceleration. The speed of the belt is $\sqrt{\frac{g h}{6}}$ and the coefficient of friction is $\frac{5}{3 \sqrt{3}}$. The time taken by the person to reach from $A$ to $B$ with the maximum possible acceleration is

$A$ block of a certain mass is placed on a rough inclined plane. The angle between the plane and the horizontal is $30^{\circ}$. The coefficients of static and kinetic friction between the block and the inclined plane are $0.6$ and $0.5$ respectively. Then,the magnitude of the acceleration of the block is [Take $g = 10 \ ms^{-2}$]