Consider the diagram shown below in which two masses of $m$ and $2 m$ are placed on a fixed triangular wedge. The coefficient of friction between block $A$ and the wedge is $2 / 3$, while that for block $B$ and the wedge is $1 / 3$
AIIMS 2015, Difficult
Download our app for free and get startedPlay store
(a)

Given,

$\mu_2=\frac{2}{3} \text { and } \mu_0=\frac{1}{3}$

Let the acceleration of the whole system be a then,

As per the diagram,

For block $B$,

$2 mg \cos 45^{\circ}+2 ma = T +\mu_0 N _{ b }$

$N _{ b }=2 mg \sin 45^{\circ}$

And, For block $A$,

$T =m g \cos 45^{\circ}+\mu_g N_a$

$N_{ a }=m g \sin 45^{\circ}$

So,

$T=m g \cos 45^{\circ}+\mu_2 m g \sin 45^{\circ} \ldots \ldots$

From eq $(1)$ and $(2)$

$2 m g \cos 45^{\circ}+2 ma =m g \cos 45^{\circ}+\mu_2 m g \sin 45^{\circ}+\mu_0 2 m g \sin 45^{\circ}$

After solving, We get $a =0$

So the acceleration of the block $A$ will be zero.

art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    A small block of mass $m$ is projected horizontally with speed $u$ where friction coefficient between block and plane is given by $\mu = cx$, where $x$ is displacement of the block on plane. Find maximum distance covered by the block 
    View Solution
  • 2
    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
    View Solution
  • 3
    A body of mass $2\,kg$ slides down with an acceleration of $3\,m/s^2$ on a rough inclined plane having a slope of $30^o$ . The external force required to take the same body up the plane with the same acceleration will be  $... N$ $(g\, = 10\, m/s^2)$
    View Solution
  • 4
    A block of mass $2 \,kg$ is kept on the floor. The coefficient of static friction is $0.4$. If a force F of $2.5$ Newtons is applied on the block as shown in the figure, the frictional force between the block and the floor will be ........ $N$ 
    View Solution
  • 5
    A block of mass $15 \,kg $ is resting on a rough inclined plane as shown in figure. The  block is tied up by a horizontal string which has tension of $50\,N$. The minimum  coefficient of friction between the surfaces of contact is $(g = 10\,m/s^2)$
    View Solution
  • 6
    A car is moving on a circular level road of curvature $300\,metres.$ If the coefficient of friction is $0.3$ and acceleration due to gravity is $10\,m/s^2,$ the maximum speed the car can have is ........ $km/hr$ 
    View Solution
  • 7
    A block of mass $10 \,kg$. moving with acceleration $2 \,m / s ^2$ on horizontal rough surface is shown in figure The value of coefficient of kinetic friction is ...........
    View Solution
  • 8
    A vehicle is moving with a velocity $v$  on a curved road of width $b$  and radius of curvature $R.$  For counteracting the centrifugal force on the vehicle, the difference in elevation required in between the outer and inner edges of the road is
    View Solution
  • 9
    A cart moves with a constant speed along $a$ horizontal circular path. From the cart, $a$ particle is thrown up vertically with respect to the cart
    View Solution
  • 10
    A force acts on a block as shown in figure. Find time when block loses contact with surface.
    View Solution