A plank with a box on it at one end is gradually raised about the other end. As the angle of inclination with the horizontal reaches 30

A block of mass 10 kg is in contact against the inner wall of a hollow cylindrical drum of radius 1 m. The coefficient of friction between the block and the inner wall of the cylinder is 0.1. The minimum angular velocity needed for the cylinder to keep the block stationary when the cylinder is [...]

A block of mass m is in contact with the cart as shown in figure. The coefficient of static friction between the block and the cart is . The acceleration of the cart that will prevent the block from falling satisfies A plank with a box on it at one end is gradually raised about [...]

The upper half of an inclined plane of inclination θ is perfectly smooth while the lower half rough. A block starting from rest at the top of the plane will again come to rest at the bottom if the coefficient of friction between the block and the lower half of the plane is given by. [...]

A plank with a box on it at one end is gradually raised about the other end. As the angle of inclination with the horizontal reaches 30, the box starts to slip and slides 4.0 m down the plank in 4.0 s. The coefficients of static and kinetic friction between the box and the plank [...]