The upper half of an inclined plane of inclination  is perfectly smooth while lower half is 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 lower half of the plane is given by

A horizontal force of is necessary to just hold a block stationary against a wall. The coefficient of friction between the block and the wall is 0.2 . The weight of the block is

A block  is pushed momentarily along a horizontal surface with an initial velocity . If  is the coefficient of sliding friction between B and the surface, block B will come to rest after a time 

A body of mass  is placed on a horizontal surface having kinetic friction 0.4 and static friction 0.5 . If the force applied on the body is , then the frictional force acting on the body will be  

A mass  is placed on a rough horizontal plane, coefficient of friction between then is M. Another mass  hung from the string connected by frictionless pulley as shown in the figure. Then 

A block rests on a rough inclined plane making an angle of  with the horizontal. The coefficient of static friction between the block and the plane is 0.8 . If the frictional force on the block is , the mass of the block (in  ) is (take )

The minimum force required to start pushing a body up rough (frictional coefficient  ) inclined plane is  while the minimum force needed to prevent it from sliding down is . If the inclined plane makes an angle  from the horizontal such that  then the ratio  is 

A body starts from rest on a long inclined plane of slope . The coefficient of friction between the body and the plane varies as , where  is distance travelled down the plane. The body will have maximum speed (for  ) when 

A  force acts horizontally on a block of  placed on a horizontal rough surface of coefficient of friction . If the acceleration due to gravity  is taken as , the acceleration of the block (in  ) is         

A block of mass  is held against a wall applying a horizontal force of  on the block. If the coefficient of friction between the block and the wall is 0.5 , the magnitude of the frictional force acting on the block is: