Answer:
No, the farmer is not able to move the mule.
Explanation:
Mass =100 kg
Force=F=800 N
The coefficient between the mule and the ground=

Static friction force,f=
Normal force=N=mg
Static friction force,f=
Using 
F<f
Static friction force is greater than applied force.
Therefore , the farmer is not able to move the mule.
the machine shown in the diagram is called a tramp.
the height of the tramp is 5 and the length is 12
As stated in the statement, we will apply energy conservation to solve this problem.
From this concept we know that the kinetic energy gained is equivalent to the potential energy lost and vice versa. Mathematically said equilibrium can be expressed as


Where,
m = mass
= initial and final velocity
g = Gravity
h = height
As the mass is tHe same and the final height is zero we have that the expression is now:






Answer:
They are able to balance torques due to gravity.

Explanation:
When two friends of different masses will balance themselves on see saw then at equilibrium position the see saw will remain horizontal
This condition will be torque equilibrium position where the see saw will not rotate
Here we can say

here we know that force is due to weight of two friends
and their positions are different with respect to the lever about which see saw is rotating
since both friends are of different weight so they will balance themselves are different positions as per above equation