Answer:
Use of telemetry and radar astronomy
Explanation:
An astronomical Unit (AU) is a unit of measuring distances in outer space, which is based on the approximate distance between the earth and the Sun.
After several years of trying to approximate the distance between the Sun and the Earth using several methods based on geometry and some other calculations, advancements in technology made available the presence of special motoring equipment, which can be placed in outer space to remotely monitor and measure the position of the sun.
The use of direct radar measurements to the sun (radar astronomy) have also made the determination of the AU more accurate.
A standard radar pulse of known speed is sent to the Sun, and the time with which it takes to return is measured, once this is recorded, the distance between the Earth and the Sun can be calculated using
distance = speed X time.
However, most of these means have to be corrected for parallax errors
Answer:
The velocity of the frozen rock at 
is -14.711 meters per second.
Explanation:
The frozen rock experiments a free fall, which is a type of uniform accelerated motion due to gravity and air viscosity and earth's rotation effect are neglected. In this case, we need to find the final velocity (
), measured in meters per second, of the frozen rock at given instant and whose kinematic formula is:
(Eq. 1)
Where:
- Initial velocity, measured in meters per second.
- Gravity acceleration, measured in meters per square second.
- Time, measured in seconds.
If we get that 
, 
and 
, then final velocity is:
The velocity of the frozen rock at is -14.711 meters per second.
Answer:4. Two charged objects have a repulsive force of 0.080 N. If the distance separating the objects is tripled, then what is the new force? Explanation: The electrostatic force is inversely related to the square of the separation distance.
Explanation:
To determine the centroid of the object first moment of area is used.
To predict the resistance of a shape to bending and deflection which are directly proportional, second moment of area is used.
Atomic number=Proton count
Atomic mass=Proton count+ neutron count
Neuton Count=Atomic mass-Proton count
Proton count=Atomic number=27
Mass number=74
Neuton count= 74-27=47
