Answer:
no I don’t think there can be so my answer is No.
Okay then yes sorry that I must have gotten it wrong before.
Explanation:
 
        
                    
             
        
        
        
Because upward buoyant force is slightly higher than gravitation force for this particular  object 
        
             
        
        
        
By the formula of torque balance we know that

here we know that
r = distance of force 
F = applied force
so here we know that as we will take large edge knife then the distance of force will increase
due to this the torque will also increase in it so it is easy to pear it
So here we can say


so output force will increase in this case
So here the correct answer would be
<em>b. the longer the knife, the stronger the output force</em>
 
        
             
        
        
        
A) it is always changing direction
        
                    
             
        
        
        
Answer:
The new separation distance between adjacent bright fringes will be <u>4 mm</u>
Explanation:
Since, the distance between adjacent bright fringes is given by the formula:
Δx₁ = λL/d = 2 mm  -------- eqn (1)
where,
Δx = Distance between adjacent bright fringes
λ = wavelength of light = constant for both cases
L = Distance between the slits and the screen
d = slit separation 
Now, for the second case:
Slit Separation = d/2
Therefore,
Δx₂ = λL/(d/2)
Δx₂ = 2(λL/d)
using eqn (1), we get:
Δx₂ = 2 Δx₁
Δx₂ = 2(2 mm)
<u>Δx₂ = 4 mm</u>