Physics-
General
Easy
Question
A rough vertical board has an acceleration ‘a’ so that a 2 kg block pressing against it does not fall. The coefficient of friction between the block and the board should be
The correct answer is:
For the limiting condition upward friction force between board and block will balance the weight of the block.
i.e.
Þ
Þ
Þ
Related Questions to study
Physics-
Block A weighing 100 kg rests on a block B and is tied with a horizontal string to the wall at C. Block B weighs 200 kg. The coefficient of friction between A and B is 0.25 and between B and the surface is 1/3. The horizontal force P necessary to move the block B should be
Block A weighing 100 kg rests on a block B and is tied with a horizontal string to the wall at C. Block B weighs 200 kg. The coefficient of friction between A and B is 0.25 and between B and the surface is 1/3. The horizontal force P necessary to move the block B should be
Physics-General
Physics-
A body of weight 50 N placed on a horizontal surface is just moved by a force of 28.2 N. The frictional force and the normal reaction are
A body of weight 50 N placed on a horizontal surface is just moved by a force of 28.2 N. The frictional force and the normal reaction are
Physics-General
Physics-
A 40 kg slab rests on a frictionless floor as shown in the figure. A 10 kg block rests on the top of the slab. The static coefficient of friction between the block and slab is 0.60 while the kinetic friction is 0.40. The 10 kg block is acted upon by a horizontal force 100 N. If , the resulting acceleration of the slab will be
A 40 kg slab rests on a frictionless floor as shown in the figure. A 10 kg block rests on the top of the slab. The static coefficient of friction between the block and slab is 0.60 while the kinetic friction is 0.40. The 10 kg block is acted upon by a horizontal force 100 N. If , the resulting acceleration of the slab will be
Physics-General
Physics-
A body of mass m rests on horizontal surface. The coefficient of friction between the body and the surface is If the mass is pulled by a force P as shown in the figure, the limiting friction between body and surface will be
A body of mass m rests on horizontal surface. The coefficient of friction between the body and the surface is If the mass is pulled by a force P as shown in the figure, the limiting friction between body and surface will be
Physics-General
Physics-
A block P of mass m is placed on a frictionless horizontal surface. Another block Q of same mass is kept on P and connected to the wall with the help of a spring of spring constant k as shown in the figure. is the coefficient of friction between P and Q. The blocks move together performing SHM of amplitude A. The maximum value of the friction force between P and Q is
A block P of mass m is placed on a frictionless horizontal surface. Another block Q of same mass is kept on P and connected to the wall with the help of a spring of spring constant k as shown in the figure. is the coefficient of friction between P and Q. The blocks move together performing SHM of amplitude A. The maximum value of the friction force between P and Q is
Physics-General
Physics-
What is the maximum value of the force F such that the block shown in the arrangement, does not move
What is the maximum value of the force F such that the block shown in the arrangement, does not move
Physics-General
Physics-
A block of mass 0.1 kg is held against a wall by applying a horizontal force of 5 N 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
A block of mass 0.1 kg is held against a wall by applying a horizontal force of 5 N 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
Physics-General
Physics-
A block of mass m lying on a rough horizontal plane is acted upon by a horizontal force P and another force Q inclined at an angle to the vertical. The block will remain in equilibrium, if the coefficient of friction between it and the surface is
A block of mass m lying on a rough horizontal plane is acted upon by a horizontal force P and another force Q inclined at an angle to the vertical. The block will remain in equilibrium, if the coefficient of friction between it and the surface is
Physics-General
Physics-
A 10 kg block is connected to an empty 1kg bucket by a cord running over a friction less pulley. The static friction coefficient is 0.4 and the kinetic friction between the table and block is 0.3. Sand is gradually added to the bucket until the system just begins to move. The mass of sand added to the bucket and the acceleration (in m/s2) of the system respectively ( g = acceleration due to gravity)
A 10 kg block is connected to an empty 1kg bucket by a cord running over a friction less pulley. The static friction coefficient is 0.4 and the kinetic friction between the table and block is 0.3. Sand is gradually added to the bucket until the system just begins to move. The mass of sand added to the bucket and the acceleration (in m/s2) of the system respectively ( g = acceleration due to gravity)
Physics-General
Physics-
A plank having mass M is placed on smooth horizontal surface. Block of mass m is placed on it coefficient of friction between block and plank is , where k is constant and x is relative displacement between block and plank. A force F is applied on block where F = at, where a = 10; t is in second. Find t0 when relative motion will occur between block and plank
A plank having mass M is placed on smooth horizontal surface. Block of mass m is placed on it coefficient of friction between block and plank is , where k is constant and x is relative displacement between block and plank. A force F is applied on block where F = at, where a = 10; t is in second. Find t0 when relative motion will occur between block and plank
Physics-General
Physics-
Initial velocity of the block while external force on it is . It coefficient of static and kinetic friction are .3 and .2 respectively then distance traveled by the block in 12 sec. (g = 10 m/s2) is:
Initial velocity of the block while external force on it is . It coefficient of static and kinetic friction are .3 and .2 respectively then distance traveled by the block in 12 sec. (g = 10 m/s2) is:
Physics-General
Physics-
In the system shown, the acceleration of the wedge of mass 5M is (there is no friction anywhere)
In the system shown, the acceleration of the wedge of mass 5M is (there is no friction anywhere)
Physics-General
Physics-
A particle starts at ‘A’ with initial speed . It moves along a circular path under the action of a variable
force which is always directed towards ‘B”. A and B are end points of a diameter. When it reaches the point ‘P’ as shown , the speed is (Neglect the effect of gravity).
A particle starts at ‘A’ with initial speed . It moves along a circular path under the action of a variable
force which is always directed towards ‘B”. A and B are end points of a diameter. When it reaches the point ‘P’ as shown , the speed is (Neglect the effect of gravity).
Physics-General
Physics-
A bead of mass m is fitted on a rod and can move on it without friction. Initially the bead is at the middle of the rod and the rod moves translationally in a vertical plane with an acceleration in a direction forming an angle with the horizontal plane. The acceleration of bead with respect to rod is
A bead of mass m is fitted on a rod and can move on it without friction. Initially the bead is at the middle of the rod and the rod moves translationally in a vertical plane with an acceleration in a direction forming an angle with the horizontal plane. The acceleration of bead with respect to rod is
Physics-General
Physics-
A lens when placed on a plane mirror then object needle and its image coincide at 15 cm. The focal length of the lens is
A lens when placed on a plane mirror then object needle and its image coincide at 15 cm. The focal length of the lens is
Physics-General