Refer to the diagram shown below.
The suspended wire is in the shape of a parabola defined by the equation
y = ax²
where a = a positive constant.
The derivative of y with respect to x is y' = 2ax.
The vertex is at (0,0) and the line of symmetry is x = 0.
The suspended length is 41 ft, therefore half the suspended length is 20.5 ft.
The length between x = 0 and x = 20 is given by
![\int _{0}^{20} \sqrt{1+[y'(x)]^{2}} \, dx = \int_{0}^{20} \sqrt{1+4a^{2}x^{2}} \, dx =20.5](https://tex.z-dn.net/?f=%5Cint%20_%7B0%7D%5E%7B20%7D%20%5Csqrt%7B1%2B%5By%27%28x%29%5D%5E%7B2%7D%7D%20%5C%2C%20dx%20%3D%20%5Cint_%7B0%7D%5E%7B20%7D%20%5Csqrt%7B1%2B4a%5E%7B2%7Dx%5E%7B2%7D%7D%20%5C%2C%20dx%20%3D20.5)
Because we do not know the value of a, we shall find it numerically.
Define the function

The plot for f(a) versus a yields an approximate solution (from Matlab) of a = 0.01 (shown in the figure).
Therefore
y = 0.01x²
When x = 20 ft, h = 0.01(400) = 4 ft
Because the vertex of the parabola is 19 ft above ground, the support points for the wire are 19 + h = 23 ft above ground.
Answer: 23.00 ft
Answer: <u>To establish a point from which to measure a future distance, or if movement has occurred.</u>
Explanation:
A reference point is a point with respect to which one comes to know whether any movement has occurred or not. A still point is required. When the object changes distance from that point, it means that object has moved. The distance can be calculated from one point to another.
Therefore, A reference point is used to establish a point from which future distance or if movement has occurred is detected.
Answer:
i dont know but what i could say is you could go on and ask the question and it would help you
Explanation:
Answer:
32 W.
Explanation:
Power: This can be defined as the ratio of energy to time. The S.I unit of power is watt(W). The formula for power is given as,
P = W/t.................... Equation 1
Where P = power, W = work done, t = time.
Given: W = 400 J, t = 10 s.
Substitute into equation 1
P = 400/10
P = 40 W.
If the motors that is choose is 80% efficient,
P' = P(0.8)
Where P' = minimum power
P' = 40(0.8)
P' = 32 W.