Answer:
a = 12 [m/s²]
Explanation:
To solve this problem we must use Newton's second law which tells us that the sum of forces on a body is equal to the product of mass by acceleration.
ΣF = m*a
where:
ΣF = sum of forces acting on a body [N] (units of Newtons)
m = mass = 0.5 [kg]
a = acceleration [m/s²]
Let's take the direction of positive forces to the right and negative forces directed to the left
2 + 8 - 4 = 0.5*a
6 = 0.5*a
a = 12 [m/s²]
The theodolite is a precision measuring device used to measure horizontal and vertical angles. It works with a combination of: (1) optical plummets, which is used to ensure that it is placed exactly vertical above; (2) internal spirit, which ensures that it is levelled to the horizon; and (3) graduated circles, one vertical and one horizontal, which is used to measure actual angles. The mounted telescope can swivel horizontally and vertically. If this is adjusted correctly, accurate measurements can be obtained.
Answer: potassium
Explanation: An atom of potassium would have a very easy time losing one electron to form an ionic bond with an atom of an element that would easily accept it.
Let R be radius of Earth with the amount of 6378 km h = height of satellite above Earth m = mass of satellite v = tangential velocity of satellite
Since gravitational force varies contrariwise with the square of the distance of separation, the value of g at altitude h will be 9.8*{[R/(R+h)]^2} = g'
So now gravity acceleration is g' and gravity is balanced by centripetal force mv^2/(R+h):
m*v^2/(R+h) = m*g' v = sqrt[g'*(R + h)]
Satellite A: h = 542 km so R+h = 6738 km = 6.920 e6 m g' = 9.8*(6378/6920)^2 = 8.32 m/sec^2 so v = sqrt(8.32*6.920e6) = 7587.79 m/s = 7.59 km/sec
Satellite B: h = 838 km so R+h = 7216 km = 7.216 e6 m g' = 9.8*(6378/7216)^2 = 8.66 m/sec^2 so v = sqrt(8.32*7.216e6) = 7748.36 m/s = 7.79 km/sec