Home
Class 12
PHYSICS
A block of negligible size and mass 2kg ...

A block of negligible size and mass 2kg is placed above a plank of mass 4kg and length 16m as shown in figure. A force of 44N is applied on the lower block as shown in the figure. The ground is smooth, coefficient of friction between upper and lower block is 0.2. Find the time after which the upper block will fall over.

A

1s

B

2s

C

3s

D

4s

Text Solution

Verified by Experts

The correct Answer is:
B

Fmax such that the blocks move together = `μ (M + m) g = 12N`
Hence, the block will slip over each other
`a_(2kg) = (4)/(2) = 2m//s^(2) a_(4kg) = (44 - 4)/(4) = 10 m//s^(2)`
relative to the lower block `implies a_(2kg) = 10 - 2 = 8m//s^(2)`
Hence, time for falling over `implies (1)/(2 8t^(2) = 16 implies t = 2s`
Promotional Banner

Similar Questions

Explore conceptually related problems

A force of 100N is applied on a block of mass 3kg as shown in the figure. The coefficient of friction between the surface and the block is mu=(1)/(sqrt(3) . The friction force acting on the bock is.

A force of 200N is applied as shown in the figure on block of 3 kg. The coefficient of friction between the block and the wall is 0.3. Find the friction acting on the block. (in N) {Take g = 10 m//s^(2)

A force of 0.5 N is applied on upper block as shown in figure. The work done ( in joule ) by upper block on lower block for a displacement of 3 m is :

A force of 100 N is applied on a block of mass 3kg as shown below. The coefficient of friction between wall and the block is 1//4 . The friction force acting on the block is :

A block of mass m = 2kg is accelerating by a force F = 20N applied on a smooth light pulley as shown in the figure. If the coefficient of kinetic friction between the block and the surface is mu=0.3 , find its acceleration.

A block of mass 1 kg is placed on a wedge shown in figure. Find out minimum coefficient of friction between wedge and block to stop the block on it.

A block of mass 2 kg is placed on the floor. The coefficient of static friction is 0.4. A force F of 3 N is applied on the block as shown in figure. The force of friction between the block and the floor is (Take g=10 m s^(-2) )

A block of mass m=4kg is placed oner a rough inclined plane as shown in figure. The coefficient of friction between the block and the plane is mu=0.5 . A force F=10N is applied on the block at an angle of 30^(@) .

A block of mass 2kg is kept on the floor. The coefficient of static friction is 0.4 . If a force F of 2.5N is applied on the block as shown in the figure, the frictional force between the block and the floor will be.