A reasonable estimate is 1 x 10^3 feet. By elimination, the first and second can't be since it will yield a negative answer and height can't be negative. Next, the fourth option will yield almost 1800 miles tall which is an impossible height. So the third is the reasonable estimate. Hope it helps.
Answer:
a vacuum formed above the column of mercury in a mercury barometer.
I think analog but I could be wrong
Answer:
its speed when its height was half that of its starting point is 25.46 m/s
Explanation:
Given;
final speed of the roller coaster, v = 36 m/s
Applying general equation of motion;
V² = U² + 2gh
where;
V is the final speed of the roller coaster
U is the initial speed of the roller coaster = 0
h is the height attained at a given velocity
36² = 0 + (2 x 9.8)h
1296 = 19.6 h
h = 1296/19.6
h = 66.1224 m
when its height was half that of its starting point, h₂ = ¹/₂ h
h₂ = ¹/₂(66.1224 m) = 33.061 m
At h = 33.061 m, V = ?
V² = U² + 2gh
V² = 0 + 2 x 9.8 x 33.061
V² = 648
V = √648
V = 25.46 m/s
Therefore, its speed when its height was half that of its starting point is 25.46 m/s