Answer:
(a)
(b)
Explanation:
The average power is defined as the amount of work done during a time interval:
According to work-energy theorem, the work done is equal to the change in kinetic energy. So, we have:
Recall that the weight is given by:
The car accelerates uniformly from rest (). Replacing (3) in (2), we have:
(a) Finally, we replace this in (1):
(b)
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°
