Question

118. Consider the system shown being pushed by
constant horizontal force equal to 10 N as show
There is friction between the blocks of masse
2 kg and 2 kg. Other surfaces are smoott
Minimum coefficient of friction between the block
of 2 kg and 2 kg for no slipping is
(Take g = 10 m/s2)


(1) 2
(2) 3
(3) 4
(4) 5​

Answer 1

Answer:

2 is answer

plzzzzzzz make it a brainlist answer

Answer 2

Minimum coefficient of friction between the block  of 2 kg and 2 kg for no slipping is 5, option (4) is correct.

Explanation:

1. Here total mass of object is 5 kg.

2. So from newton second law (F = ma)

 Where F = Net force acting on object i.n direction of acceleration in Newton.

             m = mass of object in kg.

             a = acceleration of object ($\frac{m}{s^{2}}$)

3. On considering three object

       From newton second law

       F = m×a

       10 = 5×a

      So acceleration of all three object in horizontal rightward direction is  

     a =2($\frac{m}{s^{2}}$)

4. Now consider right side object which mass is 2 kg. On 2 kg object there are contact reaction between middle object and extreme right side object. Let contact reaction is represented by R and its direction in towards rightward horizontal direction.

5. Now apply newton second law on rightward object in horizontal direction.

  F = m×a

Here for 2 kg object

F= R (contact reaction between object)

So

R = 2×2= 4(N)

It means that contact reaction between middle object and extreme right side object is 4 Newton.

6. Now consider middle object which mass is 2 kg. Here friction force is act in upward direction due to its tendency to move in downward.

7. Magnitude of friction force = $\mu \times R$ =$\mu \times 4$

8. Again consider force in vertical direction on middle object.

    Upward force = Friction force = $\mu \times 4$ (N)

    Downward force = weight of object = 2×g = 2×10= 20(N)

9. Middle object is in equilibrium in vertical direction so

   Upward force = Downward force

    $\mu \times 4= 20$

  So $\mu=5$

7.  above answer is correct for no slipping case. But i want to add one line here

 here object not slip but have tendency to rotate in anticlockwise direction due to couple of friction force and weight of middle object.

8. So to avoid rotational tendency there must be friction between 1kg and 2kg.