Physics-
General
Easy
Question
Two bodies A and B of masses 10 kg and 5 kg are placed very slightly separated as shown in figure. The coefficients of friction between the floor and the blocks are as 
. Block A is pushed by an external force F. The value of F can be changed. When the welding between block A and ground breaks, block A will start pressing block B and when welding of B also breaks, block B will start pressing the vertical wall 
If 
, with how much force does block A presses the block B
- 10 N
- 20 N
- 30 N
- Zero
The correct answer is: Zero
Related Questions to study
physics-
STATEMENT-1 : A fixed wedge of inclination 
lies on horizontal table. x and y axes are drawn on inclined surface as shown, such that x axis is horizontal and y-axis is along line of greatest slope. A block of mass m is placed (at rest) on inclined surface at origin. The coefficient of friction between block and wedge is 
, such that 
. Then a force 
applied to block parallel to inclined surface and along x-axis can move the block along x-axis
STATEMENT-2 : To move the block placed at rest on rough inclined surface along the inclined surface, the net force on block (except frictional force) should be greater than 
. (N = normal reaction on block).
STATEMENT-1 : A fixed wedge of inclination lies on horizontal table. x and y axes are drawn on inclined surface as shown, such that x axis is horizontal and y-axis is along line of greatest slope. A block of mass m is placed (at rest) on inclined surface at origin. The coefficient of friction between block and wedge is , such that . Then a force applied to block parallel to inclined surface and along x-axis can move the block along x-axis
STATEMENT-2 : To move the block placed at rest on rough inclined surface along the inclined surface, the net force on block (except frictional force) should be greater than . (N = normal reaction on block).
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I and II reagents are
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The packing efficiency of the two-dimensional square unit cell shown below is
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A particle A of mass 
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physics-General
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STATEMENT-1 : A block of mass m is placed at rest on rough horizontal surface. The coefficient of friction between the block and horizontal surface is 
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)
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physics-General
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In the following figure, find the direction of friction on the blocks and ground respectively
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physics-General
physics-
A mass m is supported as shown in the figure by ideal strings connected to a rigid wall and to a mass 3m at rest on a fixed horizontal surface. The string connected to larger mass is horizontal, that connected to smaller mass is vertical and the one connected to wall makes an angle 
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A mass m is supported as shown in the figure by ideal strings connected to a rigid wall and to a mass 3m at rest on a fixed horizontal surface. The string connected to larger mass is horizontal, that connected to smaller mass is vertical and the one connected to wall makes an angle with horizontal. Then the minimum coefficient of static friction between the larger mass and the horizontal surface that permits the system to remain in equilibrium in the situation shown is:
physics-General
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Given 
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In the system shown in figure the friction coefficient between ground and bigger block is . There is no friction between both the blocks. The string connecting both the block is light; all three pulleys are light and frictionless. Then the minimum limiting value of so that the system remains in equilibrium is
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physics-General
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A chain of length L is placed on a horizontal surface as shown in figure. At any instant x is the length of chain on rough surface and the remaining portion lies on smooth surface. Initially x = 0. A horizontal force P is applied to the chain (as shown in the figure ). In the duration x changes from x = 0 to x = L, for chain to move with constant speed:
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What are types of following semiconductors I and II
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chemistry-General
