Home
Class 12
PHYSICS
A cubical block (of sie 2m) of mass 20 k...

A cubical block (of sie 2m) of mass 20 kg slides on inclined plane lubricated with the oil of viscosity `eta=10^(-1)` poise with constant velocity of 10 m/s find out the thickness of layer of liquid (`g=10m//s^(2)`)

Text Solution

Verified by Experts

The correct Answer is:
4

` F = F ' eta A (dv )/ (dz ) = m g sin theta , (dv )/(dz ) = (v)/(h) `
` 20 xx 10 xx sin 30 ^@ = eta xx 4 xx (10)/(h) `
` h = (40 xx 10 ^(-2))/(100) - [eta = 10 ^(-1) ` poise ` = 10 ^(-2) N - sec - m ^(-2) ] `
` = 4 xx 10 ^(-3 ) m = 4mm `
Promotional Banner

Similar Questions

Explore conceptually related problems

A cubical block (of side 2 m ) of mass 20 kg slides on inclined plane lubricated with the oil of viscosity eta=10^(-1) with constant velocity of 10 ms^(-1) . Find out the thickness of the layer of liquid (take g = 10 ms^(-2) ).

A wooden box of mass 8kg slides down an inclined plane of inclination 30^(@) to the horizontal with a constant acceleration of 0.4ms^(-2) What is the force of friction between the box and inclined plane ? (g = 10m//s^(2)) .

A solid cylinder rolls down an inclined plane of height 3m and reaches the bottom of plane with angular velocity of 2sqrt2 rad//s . The radius of cylinder must be [take g=10m//s^(2) ]

A cylinder of mass 1/sqrt(3)kg is placed on the corner of two inclined planes as shown in the figure.Find the normal reaction in newtons at contact point of cylinder with the slope of inclination 30^(@) g=10m/s^(2)

Block of mass 10 kg is moving on inclined plane with constant velocity 10 m/s. The coedfficient of kinetic friction between incline plane and block is :-

(a) A block slides down an incline of angle 45^(@) with an acceleration (g)/(2 sqrt(2)) . Find the friction coefficient. (b) A block slides down at 45^(@) inclined plane in twice the time it takes to slide down a smooth 45^(@) incline. What is friction co-efficient between the block and the incline? ( c) A block slides down on a rough inclined plane of inclination 30^(@) with constant velocity. If this block is projected up the plane with a velocity of 10 m//s , then at what distance along the inclined plane , the block will come to rest? (d) A body is launched up on a rough inclined plane of inclination theta . If time of ascent is half of time of descent, find the friction coefficient.

An external force 6N is applied on a sphere of radius R = 10 cm of mass 1 kg and the sphere moves in a liquid with a constant velocity 5 m/s making 530 with the horizontal.The coefficient of viscosity of the liquid is 20//(6pi), in S.I units. (Take g=10 m//s^(2) )

A mass of 1 kg is just able to slide down the slope of an inclined rough surface when the angle of inclination is 60^(@) The minima force necessary to pull the mass up the inclined plane is: (g=10 m//s^(2))

A body of 5 kg weight kept on a rough inclined plane of angle 30^(@) starts sliding with a constant velocity. Then the coefficient of friction is (assume g=10m//s^(2) )