Answer:
Rectangular path
Solution:
As per the question:
Length, a = 4 km
Height, h = 2 km
In order to minimize the cost let us denote the side of the square bottom be 'a'
Thus the area of the bottom of the square, A = 
Let the height of the bin be 'h'
Therefore the total area, 
The cost is:
C = 2sh
Volume of the box, V =
(1)
Total cost,
(2)
From eqn (1):

Using the above value in eqn (1):


Differentiating the above eqn w.r.t 'a':

For the required solution equating the above eqn to zero:


a = 4
Also

The path in order to minimize the cost must be a rectangle.
so the 1st on is the one on the left, middle is right and the 3rd one is the right one
6050 J is the kinetic energy at D
<u>Explanation:</u>
In physics, the object's kinetic energy (K.E) defined as the energy it possesses during movement. It can be defined as the required work to accelerate a certain body weight in order to rest at a certain speed. When the body receives this energy as it speeds up (accelerates), it retains this energy unless speed varies. The equation is given as,

Where,
m - mass of an object
v - velocity of the object
Here,
Given data:
m = 100 kg
v = 11 m/s
By substituting the given values in the above equation, we get

Answer:
Distance= 2.3864m
Explanation:
So that the balance is in equilibrium parallel to the floor, we must match the moment each man makes with respect to the pivot point.
In many cases the point of application of force does not coincide with the point of application in the body. In this case the force acts on the object and its structure at a certain distance, by means of an element that transfers that action of this force to the object.
This combination of force applied by the distance to the point of the structure where it is applied is called the moment of force F with respect to the point. The moment will attempt a rotation shift or rotation of the object. The distance from the force to the point of application is called the arm.
Mathematically it is calculated by expression:
M= F×d
The moment caused by the first man is:
M1= 75kg × (9.81m/s²) × 1.75m= 1287.5625 N×m
The moment caused by the second man must be equal to that caused by the first by which:
M2= 1287.5625 N×m= 55kg × (9.81m/s²) × distance ⇒
⇒distance= (1287.5625 N×m)/( (55kg × (9.81m/s²) )= 2.3864m
At this distance from the pivot point, the second should sit down so that the balance is balanced parallel to the ground.
I think this is correct, but I am not entirely certain.
Find the force constant of the spring:
F = - KX
(0 - 62.4) = -K(0.172m)
-362.791 = -K
362.791 N/m = K
Find the work done in stretching the spring:
W = (1/2)KX
W = (1/2)(362.791)(0.172m)
W = 31.2 J