Nicolaus Copernicus
This theory was first proposed by Nicolaus Copernicus. Copernicus was a Polish astronomer. He first published the heliocentric system in his book: De revolutionibus orbium coelestium, "On the revolutions of the heavenly bodies," which appeared in 1543.
Answer:
Vertical Height = 0.784 meter, Speed back at starting point = 10 m/s
Explanation:
Given Data:
V is the overall velocity vector, and are its initial vertical and horizontal components
To find:
Max Height achieved
Calculation:
1) Using the equation of motion, we know
2) In terms of gravity height and the vertical component of Velocity .
3) As as at maximum height the vertical component of velocity is zero maximum height achieved
putting values
4)
5) As for the speed when it reaches back its starting point, it will have a speed similar to its launching speed, the reason being the absence of air friction (Air drag)
Answer:
option C
Explanation:
given,
force act on west = 20 lb
force act at 45° east of north = 80 lb
magnitude of force = ?
∑ F y = 80 cos 45⁰
F y = 56.57 lb
magnitude of forces in x- direction
∑ F x = -20 + 80 sin 45⁰
= 36.57 lb
net force
F =
F =
F = 67.36 lb≅ 67 lb
hence, the correct answer is option C