Answer: the angle between the resultant vector and the vector of the 18 pound is 28°
Explanation:
given that data in the question; as its interpreted in the diagram below;
from the cosine rule, we know that;
a² = b² + c² - 2bc
so
(13)² = (6)² + (18)² - (2 × 6 × 18 ) cos∅
169 = 36 + 324 - 216cos∅
169 = 360 - 216cos∅
216cos∅ = 360 - 169
216cos∅ = 191
cos∅ = 0.8842
∅ = cos⁻¹ ( 0.8842 )
∅ = 27.8° ≈ 28° {nearest whole number}
Therefore the angle between the resultant vector and the vector of the 18 pound is 28°
Air is a poor conductor of heat. The air trapped between the two panes is a pretty good <em>insulator</em>. It does a lot to prevent heat from flowing through the windows ... keeping heat IN during the Winter, and OUT during the Summer.
You get circular motion, where the acceleration is pointing towards the center of the circle, as long as they are constant, and not fluctuating.