Answer:
x = 3.76 cm
y = 3.76 cm
Explanation:
This composite shape can be modeled as a square (7.2 cm × 7.2 cm) minus a quarter circle in the lower left corner (3.6 cm radius) and a right triangle in the upper right corner (3.6 cm × 3.6 cm).
The centroid of a square (or any rectangle) is at x = b/2 and y = h/2.
The centroid of a quarter circle is at x = y = 4r/(3π).
The centroid of a right triangle is at x = b/3 and y = h/3.
Build a table listing each shape, the coordinates of its centroid (x and y), and its area (A). Use negative areas for the shapes that are being subtracted.
Next, multiply each coordinate by the area (Ax and Ay), sum the results (∑Ax and ∑Ay), then divide by the total area (∑Ax / ∑A and ∑Ay / ∑A). The result will be the x and y coordinates of the center of mass.
See attached image.
Answer:
1.98 m/s
Explanation:
To solve this, we would be using the law of conservation of energy, i.e total initial energy is equal to total final energy.
E(i) = E(f)
mgh = ½Iw² + ½mv²
Recall, v = wr, thus, w = v/r
Also, I = ½mr²
I = 0.5 * 5 * 2²
I = 10 kgm²
Remember,
mgh = ½Iw² + ½mv²
Substituting w for v/r, we have
mgh = ½I(v/r)² + ½mv²
Now, putting the values in the equation, we have
5 * 9.8 * 0.3 = ½ * 10 * (v/2)² + ½ * 5 * v²
14.7 = 1.25 v² + 2.5 v²
14.7 = 3.75 v²
v² = 14.7/3.75
v² = 3.92
v = √3.92
v = 1.98 m/s
Thus, the speed is 1.98 m/s
Answer:
Heat lost thru doors & windows = (100 - 75 - 5) = 20
20% is the fraction of heat lost thru doors and windows
One wants to obtain the largest savings per unit of cost
roof:
200 / 600 = 1/3
150 / 1000 = .15
40 / 2300 = .017
The largest of these is 1/3 so the most benefit would be obtained by insulating the roof
Since heat loss thru the roof depends on heat loss thru the attic, this is the most cost effective in reducing heat loss
The more the difference in temperature between the ceiling and roof (attic) the more heat will be lost thru the roof, so insulating the roof will decrease the heat loss of the attic
Strain it , the sand didn’t dissolve in the solution it just settled in the bottom
Net force is the total of all forces acting in the object.
